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Borel A, Rapisarda F, Doorn SK, Voisin C, Chassagneux Y. Luminescence Properties of Closely Packed Organic Color Centers Grafted on a Carbon Nanotube. Nano Lett 2024; 24:3456-3461. [PMID: 38457689 DOI: 10.1021/acs.nanolett.4c00127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/10/2024]
Abstract
We report on the photoluminescence of pairs of organic color centers in single-wall carbon nanotubes grafted with 3,5-dichlorobenzene. Using various techniques such as intensity correlations, superlocalization microscopy, and luminescence excitation spectroscopy, we distinguish two pairs of color centers grafted on the same nanotube; the distance between the pairs is on the order of several hundreds of nanometers. In contrast, by studying the strong temporal correlations in the spectral diffusion in the framework of the photoinduced Stark effect, we can estimate the distance within each pair to be on the order of a few nanometers. Finally, the electronic population dynamics is investigated using time-resolved luminescence and saturation measurements, showing a biexponential decay with a fast overall recombination (compatible with a fast population transfer between the color centers within a pair) and a weak delayed repopulation of the traps, possibly due to the diffusion of excitons along the tube axis.
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Affiliation(s)
- Antoine Borel
- Laboratoire de physique de l'ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, 75005 Paris, France
| | - Federico Rapisarda
- Laboratoire de physique de l'ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, 75005 Paris, France
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Christophe Voisin
- Laboratoire de physique de l'ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, 75005 Paris, France
| | - Yannick Chassagneux
- Laboratoire de physique de l'ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, 75005 Paris, France
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2
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Li MK, Riaz A, Wederhake M, Fink K, Saha A, Dehm S, He X, Schöppler F, Kappes MM, Htoon H, Popov VN, Doorn SK, Hertel T, Hennrich F, Krupke R. Electroluminescence from Single-Walled Carbon Nanotubes with Quantum Defects. ACS Nano 2022; 16:11742-11754. [PMID: 35732039 DOI: 10.1021/acsnano.2c03083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Individual single-walled carbon nanotubes with covalent sidewall defects have emerged as a class of photon sources whose photoluminescence spectra can be tailored by the carbon nanotube chirality and the attached functional group/molecule. Here we present electroluminescence spectroscopy data from single-tube devices based on (7, 5) carbon nanotubes, functionalized with dichlorobenzene molecules, and wired to graphene electrodes. We observe electrically generated, defect-induced emissions that are controllable by electrostatic gating and strongly red-shifted compared to emissions from pristine nanotubes. The defect-induced emissions are assigned to excitonic and trionic recombination processes by correlating electroluminescence excitation maps with electrical transport and photoluminescence data. At cryogenic conditions, additional gate-dependent emission lines appear, which are assigned to phonon-assisted hot-exciton electroluminescence from quasi-levels. Similar results were obtained with functionalized (6, 5) nanotubes. We also compare functionalized (7, 5) electroluminescence data with photoluminescence of pristine and functionalized (7, 5) nanotubes redox-doped using gold(III) chloride solution. This work shows that electroluminescence excitation is selective toward neutral defect-state configurations with the lowest transition energy, which in combination with gate-control over neutral versus charged defect-state emission leads to high spectral purity.
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Affiliation(s)
- Min-Ken Li
- Institute of Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Adnan Riaz
- Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt, Germany
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Martina Wederhake
- Institute of Physical and Theoretical Chemistry, Julius Maximilian University Würzburg, Würzburg 97074, Germany
| | - Karin Fink
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Avishek Saha
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Simone Dehm
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Xiaowei He
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Friedrich Schöppler
- Institute of Physical and Theoretical Chemistry, Julius Maximilian University Würzburg, Würzburg 97074, Germany
| | - Manfred M Kappes
- Institute of Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- Institute of Physical Chemistry, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | | | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Tobias Hertel
- Institute of Physical and Theoretical Chemistry, Julius Maximilian University Würzburg, Würzburg 97074, Germany
| | - Frank Hennrich
- Institute of Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Ralph Krupke
- Institute of Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt, Germany
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
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3
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Zheng Y, Han Y, Weight BM, Lin Z, Gifford BJ, Zheng M, Kilin D, Kilina S, Doorn SK, Htoon H, Tretiak S. Photochemical spin-state control of binding configuration for tailoring organic color center emission in carbon nanotubes. Nat Commun 2022; 13:4439. [PMID: 35915090 PMCID: PMC9343348 DOI: 10.1038/s41467-022-31921-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 07/04/2022] [Indexed: 12/04/2022] Open
Abstract
Incorporating fluorescent quantum defects in the sidewalls of semiconducting single-wall carbon nanotubes (SWCNTs) through chemical reaction is an emerging route to predictably modify nanotube electronic structures and develop advanced photonic functionality. Applications such as room-temperature single-photon emission and high-contrast bio-imaging have been advanced through aryl-functionalized SWCNTs, in which the binding configurations of the aryl group define the energies of the emitting states. However, the chemistry of binding with atomic precision at the single-bond level and tunable control over the binding configurations are yet to be achieved. Here, we explore recently reported photosynthetic protocol and find that it can control chemical binding configurations of quantum defects, which are often referred to as organic color centers, through the spin multiplicity of photoexcited intermediates. Specifically, photoexcited aromatics react with SWCNT sidewalls to undergo a singlet-state pathway in the presence of dissolved oxygen, leading to ortho binding configurations of the aryl group on the nanotube. In contrast, the oxygen-free photoreaction activates previously inaccessible para configurations through a triplet-state mechanism. These experimental results are corroborated by first principles simulations. Such spin-selective photochemistry diversifies SWCNT emission tunability by controlling the morphology of the emitting sites. Chemical functionalization of the sidewalls of single-wall carbon nanotubes (SWCNTs) is an emerging route to introduce fluorescent quantum defects and tailor the emission properties. Here, authors demonstrate that spin-selective photochemistry diversifies SWCNT emission tunability by controlling the morphology of the emitting sites.
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Affiliation(s)
- Yu Zheng
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
| | - Yulun Han
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, ND, 58102, USA
| | - Braden M Weight
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.,Department of Chemistry and Biochemistry, North Dakota State University, Fargo, ND, 58102, USA.,Department of Physics, North Dakota State University, Fargo, ND, 58102, USA.,Department of Physics and Astronomy, University of Rochester, Rochester, NY, 14627, USA
| | - Zhiwei Lin
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Brendan J Gifford
- Center for Nonlinear Studies, and Theoretical Division Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Ming Zheng
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Dmitri Kilin
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, ND, 58102, USA
| | - Svetlana Kilina
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, ND, 58102, USA
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
| | - Sergei Tretiak
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA. .,Center for Nonlinear Studies, and Theoretical Division Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
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4
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Zheng Y, Kim Y, Jones AC, Olinger G, Bittner ER, Bachilo SM, Doorn SK, Weisman RB, Piryatinski A, Htoon H. Quantum Light Emission from Coupled Defect States in DNA-Functionalized Carbon Nanotubes. ACS Nano 2021; 15:10406-10414. [PMID: 34061507 DOI: 10.1021/acsnano.1c02709] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Solid-state single-photon sources are essential building blocks for quantum photonics and quantum information technologies. This study demonstrates promising single-photon emission from quantum defects generated in single-wall carbon nanotubes (SWCNTs) by covalent reaction with guanine nucleotides in their single-stranded DNA coatings. Low-temperature photoluminescence spectroscopy and photon-correlation measurements on individual guanine-functionalized SWCNTs (GF-SWCNTs) indicate that multiple, closely spaced guanine defect sites within a single ssDNA strand collectively form an exciton trapping potential that supports a localized quantum state capable of room-temperature single-photon emission. In addition, exciton traps from adjacent ssDNA strands are weakly coupled to give cross-correlations between their separate photon emissions. Theoretical modeling identifies coupling mechanism as a capture of band-edge excitons. Because the spatial pattern of nanotube functionalization sites can be readily controlled by selecting ssDNA base sequences, GF-SWCNTs should become a versatile family of quantum light emitters with engineered properties.
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Affiliation(s)
- Yu Zheng
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Younghee Kim
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Andrew C Jones
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Gabrielle Olinger
- Department of Physics, University of Houston, Houston, Texas 77204, United States
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States
| | - Eric R Bittner
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States
| | - Sergei M Bachilo
- Department of Chemistry and the Smalley-Curl Institute, Rice University, Houston, Texas 77005, United States
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - R Bruce Weisman
- Department of Chemistry and the Smalley-Curl Institute, Rice University, Houston, Texas 77005, United States
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, United States
| | - Andrei Piryatinski
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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5
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Zheng Y, Weight BM, Jones AC, Chandrasekaran V, Gifford BJ, Tretiak S, Doorn SK, Htoon H. Photoluminescence Dynamics Defined by Exciton Trapping Potential of Coupled Defect States in DNA-Functionalized Carbon Nanotubes. ACS Nano 2021; 15:923-933. [PMID: 33395262 DOI: 10.1021/acsnano.0c07544] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Chemical reactions between semiconducting single-wall carbon nanotubes (SWCNTs) and single-stranded DNA (ssDNA) achieve spatially patterned covalent functionalization sites and create coupled fluorescent quantum defects on the nanotube surface, tailoring SWCNT photophysics for applications such as single-photon emitters in quantum information technologies. The evaluation of relaxation dynamics of photoluminescence (PL) from those coupled quantum defects is essential for understanding the nanotube electronic structure and beneficial to the design of quantum light emitters. Here, we measured the PL decay for ssDNA-functionalized SWCNTs as a function of the guanine content of the ssDNA oligo that dictates the red-shifting of their PL emission peaks relative to the band-edge exciton. We then correlate the observed dependence of PL decay dynamics on energy red-shifts to the exciton potential energy landscape, which is modeled using first-principles approaches based upon the morphology of ssDNA-altered SWCNTs obtained by atomic force microscopy (AFM) imaging. Our simulations illustrate that the multiple guanine defects introduced within a single ssDNA strand strongly interact to create a deep exciton trapping well, acting as a single hybrid trap. The emission decay from the distinctive trapping potential landscape is found to be biexponential for ssDNA-modified SWCNTs. We attributed the fast time component of the biexponential PL decay to the redistribution of exciton population among the lowest energy bright states and a manifold of dark states emerging from the coupling of multiple guanine defects. The long lifetime component in the biexponential decay, on the other hand, is attributed to the redistribution of exciton population among different exciton trapping sites that arise from the binding of multiple ssDNA strands along the nanotube axis. AFM measurements indicate that those trapping sites are separated on average by ∼8 nm along the nanotube axis.
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Affiliation(s)
| | - Braden M Weight
- Department of Physics, North Dakota State University, Fargo, North Dakota 58102, United States
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6
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Gifford BJ, Kilina S, Htoon H, Doorn SK, Tretiak S. Controlling Defect-State Photophysics in Covalently Functionalized Single-Walled Carbon Nanotubes. Acc Chem Res 2020; 53:1791-1801. [PMID: 32805109 DOI: 10.1021/acs.accounts.0c00210] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
ConspectusSingle-walled carbon nanotubes (SWCNTs) show promise as light sources for modern fiber optical communications due to their emission wavelengths tunable via chirality and diameter dependency. However, the emission quantum yields are relatively low owing to the existence of low-lying dark electronic states and fast excitonic diffusion leading to carrier quenching at defects. Covalent functionalization of SWCNTs addresses this problem by brightening their infrared emission. Namely, introduction of sp3-hybridized defects makes the lowest energy transitions optically active for some defect geometries and enables further control of their optical properties. Such functionalized SWCNTs are currently the only material exhibiting room-temperature single photon emission at telecom relevant infrared wavelengths. While this fluorescence is strong and has the right wavelength, functionalization introduces a variety of emission peaks resulting in spectrally broad inhomogeneous photoluminescence that prohibits the use of SWCNTs in practical applications. Consequently, there is a strong need to control the emission diversity in order to render these materials useful for applications. Recent experimental and computational work has attributed the emissive diversity to the presence of multiple localized defect geometries each resulting in distinct emission energy. This Account outlines methods by which the morphology of the defect in functionalized SWCNTs can be controlled to reduce emissive diversity and to tune the fluorescence wavelengths. The chirality-dependent trends of emission energies with respect to individual defect morphologies are explored. It is demonstrated that defect geometries originating from functionalization of SWCNT carbon atoms along bonds with strong π-orbital mismatch are favorable. Furthermore, the effect of controlling the defect itself through use of different chemical groups is also discussed. Such tunability is enabled due to the formation of specific defect geometries in close proximity to other existing defects. This takes advantage of the changes in π-orbital mismatch enforced by existing defects and the resulting changes in reactivities toward formation of specific defect morphologies. Furthermore, the trends in emissive energies are highly dependent on the value of mod(n-m,3) for an (n,m) tube chirality. These powerful concepts allow for a targeted formation of defects that emit at desired energies based on SWCNT single chirality enriched samples. Finally, the impact of functionalization with specific types of defects that enforce certain defect geometries due to steric constraints in bond lengths and angles to the SWCNT are discussed. We further relate to a similar effect that is present in systems where high density of surface defects is formed due to high reactant concentration. The outlined strategies suggested by simulations are instrumental in guiding experimental efforts toward the generation of functionalized SWCNTs with tunable emission energies.
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Affiliation(s)
| | - Svetlana Kilina
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
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7
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Wang B, Yang S, Wang Y, Kim Y, Htoon H, Doorn SK, Foran BJ, Bushmaker AW, Baker DR, Forcherio GT, Cronin SB. Formation of Brightly Luminescent MoS 2 Nanoislands from Multilayer Flakes via Plasma Treatment and Laser Exposure. ACS Omega 2020; 5:20543-20547. [PMID: 32832807 PMCID: PMC7439701 DOI: 10.1021/acsomega.0c02753] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 07/23/2020] [Indexed: 06/11/2023]
Abstract
A robust and reliable method for enhancing the photoluminescence (PL) of multilayer MoS2 is demonstrated using an oxygen plasma treatment process followed by laser exposure. Here, the plasma and laser treatments result in an indirect-to-direct band gap transition. The oxygen plasma creates a slight decoupling of the layers and converts some of the MoS2 to MoO3. Subsequent laser irradiation further oxidizes the MoS2 to MoO3, as confirmed via X-ray photoelectron spectroscopy, and results in localized regions of brightly luminescent MoS2 monolayer triangular islands as seen in high-resolution transmission electron microscopy images. The PL lifetimes are found to decrease from 494 to 190 ps after plasma and laser treatment, reflecting the smaller size of the MoS2 grains/regions. Atomic force microscopic imaging shows a 2 nm increase in thickness of the laser-irradiated regions, which provides further evidence of the MoS2 being converted to MoO3.
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Affiliation(s)
- Bo Wang
- Department
of Physics and Astronomy, University of
Southern California, Los Angeles, California 90089, United States
| | - Sisi Yang
- Department
of Physics and Astronomy, University of
Southern California, Los Angeles, California 90089, United States
| | - Yu Wang
- Mork
Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089, United States
| | - Younghee Kim
- Center
for Integrated Nanotechnologies, Materials Physics and Applications
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Han Htoon
- Center
for Integrated Nanotechnologies, Materials Physics and Applications
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Stephen K. Doorn
- Center
for Integrated Nanotechnologies, Materials Physics and Applications
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Brendan J. Foran
- The
Aerospace Corporation, El Segundo, California 90245, United States
| | - Adam W. Bushmaker
- The
Aerospace Corporation, El Segundo, California 90245, United States
| | - David R. Baker
- Sensors and
Electron Devices Directorate, U.S. Army
Research Laboratory, Adelphi, Maryland 20783, United States
| | - Gregory T. Forcherio
- Sensors and
Electron Devices Directorate, U.S. Army
Research Laboratory, Adelphi, Maryland 20783, United States
- Electro-Optic
Technology Division, Naval Surface Warfare
Center, Crane, Indiana 47522, United
States
| | - Stephen B. Cronin
- Department
of Physics and Astronomy, University of
Southern California, Los Angeles, California 90089, United States
- Ming
Hsieh Department of Electrical Engineering, University of Southern California, Los Angeles, California 90089, United States
- Mork
Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089, United States
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Kim Y, Goupalov SV, Weight BM, Gifford BJ, He X, Saha A, Kim M, Ao G, Wang Y, Zheng M, Tretiak S, Doorn SK, Htoon H. Hidden Fine Structure of Quantum Defects Revealed by Single Carbon Nanotube Magneto-Photoluminescence. ACS Nano 2020; 14:3451-3460. [PMID: 32053343 DOI: 10.1021/acsnano.9b09548] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Organic color-center quantum defects in semiconducting carbon nanotube hosts are rapidly emerging as promising candidates for solid-state quantum information technologies. However, it is unclear whether these defect color-centers could support the spin or pseudospin-dependent excitonic fine structure required for spin manipulation and readout. Here we conducted magneto-photoluminescence spectroscopy on individual organic color-centers and observed the emergence of fine structure states under an 8.5 T magnetic field applied parallel to the nanotube axis. One to five fine structure states emerge depending on the chirality of the nanotube host, nature of chemical functional group, and chemical binding configuration, presenting an exciting opportunity toward developing chemical control of magnetic brightening. We attribute these hidden excitonic fine structure states to field-induced mixing of singlet excitons trapped at sp3 defects and delocalized band-edge triplet excitons. These findings provide opportunities for using organic color-centers for spintronics, spin-based quantum computing, and quantum sensing.
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Affiliation(s)
- Younghee Kim
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Serguei V Goupalov
- Department of Physics, Jackson State University, Jackson, Mississippi 39217, United States
- Ioffe Institute, St. Petersburg 194021, Russia
| | - Braden M Weight
- Department of Physics, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Brendan J Gifford
- Center for Nonlinear Studies, Theory Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Xiaowei He
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Avishek Saha
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Mijin Kim
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - Geyou Ao
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - YuHuang Wang
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - Ming Zheng
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Sergei Tretiak
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
- Center for Nonlinear Studies, Theory Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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9
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Wang B, Yang S, Wang Y, Ahsan R, He X, Kim Y, Htoon H, Kapadia R, John DD, Thibeault B, Doorn SK, Cronin SB. Auger Suppression of Incandescence in Individual Suspended Carbon Nanotube pn-Junctions. ACS Appl Mater Interfaces 2020; 12:11907-11912. [PMID: 32083460 DOI: 10.1021/acsami.9b17519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
There are various mechanisms of light emission in carbon nanotubes (CNTs), which give rise to a wide range of spectral characteristics that provide important information. Here we report suppression of incandescence via Auger recombination in suspended carbon nanotube pn-junctions generated from dual-gate CNT field-effect transistor (FET) devices. By applying equal and opposite voltages to the gate electrodes (i.e., Vg1 = -Vg2), we create a pn-junction within the CNT. Under these gating conditions, we observe a sharp peak in the incandescence intensity around zero applied gate voltage, where the intrinsic region has the largest spatial extent. Here, the emission occurs under high electrical power densities of around 0.1 MW/cm2 (or 6 μW) and arises from thermal emission at elevated temperatures above 800 K (i.e., incandescence). It is somewhat surprising that this thermal emission intensity is so sensitive to the gating conditions, and we observe a 1000-fold suppression of light emission between Vg1 = 0 and 15 V, over a range in which the electrical power dissipated in the nanotube is roughly constant. This behavior is understood on the basis of Auger recombination, which suppresses light emission by the excitation of free carriers. Based on the calculated carrier density and band profiles, the length of the intrinsic region drops by a factor of 7-25× over the range from |Vg| = 0 to 15 V. We, therefore, conclude that the light emission intensity is significantly dependent on the free carrier density profile and the size of the intrinsic region in these CNT devices.
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Affiliation(s)
| | | | | | | | - Xiaowei He
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Younghee Kim
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | | | - Demis D John
- Nanotech, Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Brian Thibeault
- Nanotech, Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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10
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Luo Y, He X, Kim Y, Blackburn JL, Doorn SK, Htoon H, Strauf S. Carbon Nanotube Color Centers in Plasmonic Nanocavities: A Path to Photon Indistinguishability at Telecom Bands. Nano Lett 2019; 19:9037-9044. [PMID: 31682759 DOI: 10.1021/acs.nanolett.9b04069] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Indistinguishable single photon generation at telecom wavelengths from solid-state quantum emitters remains a significant challenge to scalable quantum information processing. Here we demonstrate efficient generation of "indistinguishable" single photons directly in the telecom O-band from aryl-functionalized carbon nanotubes by overcoming the emitter quantum decoherence with plasmonic nanocavities. With an unprecedented single-photon spontaneous emission time down to 10 ps (from initially 0.7 ns) generated in the coupling scheme, we show a two-photon interference visibility at 4 K reaching up to 0.79, even without applying post selection. Cavity-enhanced quantum yields up to 74% and Purcell factors up to 415 are achieved with single-photon purities up to 99%. Our results establish the capability to fabricate fiber-based photonic devices for quantum information technology with coherent properties that can enable quantum logic.
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Affiliation(s)
- Yue Luo
- Center for Nanoscale Systems , Harvard University , Cambridge , Massachusetts 02138 , United States
| | | | - Younghee Kim
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Jeffrey L Blackburn
- National Renewable Energy Laboratory , Golden , Colorado 80401 , United States
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
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11
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Gifford BJ, Saha A, Weight BM, He X, Ao G, Zheng M, Htoon H, Kilina S, Doorn SK, Tretiak S. Mod(n-m,3) Dependence of Defect-State Emission Bands in Aryl-Functionalized Carbon Nanotubes. Nano Lett 2019; 19:8503-8509. [PMID: 31682455 DOI: 10.1021/acs.nanolett.9b02926] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Molecularly functionalized single-walled carbon nanotubes (SWCNTs) are potentially useful for fiber optical applications due to their room temperature single-photon emission capacity at telecommunication wavelengths. Several distinct defect geometries are generated upon covalent functionalization. While it has been shown that the defect geometry controls electron localization around the defect site, thereby changing the electronic structure and generating new optically bright red-shifted emission bands, the reasons for such localization remain unexplained. Our joint experimental and computational studies of functionalized SWCNTs with various chiralities show that the value of mod(n-m,3) in an (n,m) chiral nanotube plays a key role in the relative ordering of defect-dependent emission energies. This dependence is linked to the complex nodal characteristics of electronic wave function extending along specific bonds in the tube, which justifies the defect-geometry dependent exciton localization. This insight helps to uncover the essential structural motifs allowing tuning the redshifts of emission energies in functionalized SWCNTs.
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Affiliation(s)
| | - Avishek Saha
- CSIR-Central Scientific Instruments Organization , Chandigarh 160030 , India
| | | | | | - Geyou Ao
- Materials Science and Engineering Division , National Institute of Standards and Technology , Gaithersburg , Maryland 20899-8540 , United States
| | - Ming Zheng
- Materials Science and Engineering Division , National Institute of Standards and Technology , Gaithersburg , Maryland 20899-8540 , United States
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12
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Kwon H, Kim M, Nutz M, Hartmann NF, Perrin V, Meany B, Hofmann MS, Clark CW, Htoon H, Doorn SK, Högele A, Wang Y. Probing Trions at Chemically Tailored Trapping Defects. ACS Cent Sci 2019; 5:1786-1794. [PMID: 31807680 PMCID: PMC6891859 DOI: 10.1021/acscentsci.9b00707] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Indexed: 05/28/2023]
Abstract
Trions, charged excitons that are reminiscent of hydrogen and positronium ions, have been intensively studied for energy harvesting, light-emitting diodes, lasing, and quantum computing applications because of their inherent connection with electron spin and dark excitons. However, these quasi-particles are typically present as a minority species at room temperature making it difficult for quantitative experimental measurements. Here, we show that by chemically engineering the well depth of sp3 quantum defects through a series of alkyl functional groups covalently attached to semiconducting carbon nanotube hosts, trions can be efficiently generated and localized at the trapping chemical defects. The exciton-electron binding energy of the trapped trion approaches 119 meV, which more than doubles that of "free" trions in the same host material (54 meV) and other nanoscale systems (2-45 meV). Magnetoluminescence spectroscopy suggests the absence of dark states in the energetic vicinity of trapped trions. Unexpectedly, the trapped trions are approximately 7.3-fold brighter than the brightest previously reported and 16 times as bright as native nanotube excitons, with a photoluminescence lifetime that is more than 100 times larger than that of free trions. These intriguing observations are understood by an efficient conversion of dark excitons to bright trions at the defect sites. This work makes trions synthetically accessible and uncovers the rich photophysics of these tricarrier quasi-particles, which may find broad implications in bioimaging, chemical sensing, energy harvesting, and light emitting in the short-wave infrared.
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Affiliation(s)
- Hyejin Kwon
- Department
of Chemistry and Biochemistry, University
of Maryland, 8051 Regents Drive, College Park, Maryland 20742, United
States
| | - Mijin Kim
- Department
of Chemistry and Biochemistry, University
of Maryland, 8051 Regents Drive, College Park, Maryland 20742, United
States
| | - Manuel Nutz
- Fakultat
für Physik, Center for NanoScience and Munich Quantum Center, Ludwig-Maximilians-Universitat München, Geschwister-Scholl-Platz 1, D-80539 München, Germany
| | - Nicolai F. Hartmann
- Center
for Integrated Nanotechnologies, Materials Physics and Applications
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Vivien Perrin
- Fakultat
für Physik, Center for NanoScience and Munich Quantum Center, Ludwig-Maximilians-Universitat München, Geschwister-Scholl-Platz 1, D-80539 München, Germany
| | - Brendan Meany
- Department
of Chemistry and Biochemistry, University
of Maryland, 8051 Regents Drive, College Park, Maryland 20742, United
States
| | - Matthias S. Hofmann
- Fakultat
für Physik, Center for NanoScience and Munich Quantum Center, Ludwig-Maximilians-Universitat München, Geschwister-Scholl-Platz 1, D-80539 München, Germany
| | - Charles W. Clark
- Joint
Quantum Institute, National Institute of
Standards and Technology, Gaithersburg, Maryland 20902, United States
| | - Han Htoon
- Center
for Integrated Nanotechnologies, Materials Physics and Applications
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Stephen K. Doorn
- Center
for Integrated Nanotechnologies, Materials Physics and Applications
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Alexander Högele
- Fakultat
für Physik, Center for NanoScience and Munich Quantum Center, Ludwig-Maximilians-Universitat München, Geschwister-Scholl-Platz 1, D-80539 München, Germany
| | - YuHuang Wang
- Department
of Chemistry and Biochemistry, University
of Maryland, 8051 Regents Drive, College Park, Maryland 20742, United
States
- Maryland
NanoCenter, University of Maryland, College Park, Maryland 20742, United States
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13
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Dervishi E, Ji Z, Htoon H, Sykora M, Doorn SK. Raman spectroscopy of bottom-up synthesized graphene quantum dots: size and structure dependence. Nanoscale 2019; 11:16571-16581. [PMID: 31460557 DOI: 10.1039/c9nr05345j] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Graphene quantum dots (GQDs) have attracted significant interest as synthetically tunable optoelectronic and photonic materials that can also serve as model systems for understanding size-dependent behaviors of related graphene structures such as nanoribbons. We present a Raman spectroscopy study of bottom-up synthesized GQDs with lateral dimensions between 0.97 to 1.62 nm, well-defined (armchair) edge type, and fully benzenoid structures. For a better understanding of observed size-dependent trends, the study is extended to larger graphene structures including nano-graphene platelets (>25 nm) and large-area graphene. Raman spectra of GQDs reveal the presence of D and G bands, as well as higher order modes (2D, D + G, and 2G). The D and G band frequencies and intensity were found to increase as GQD size increases, while higher order modes (2D, D + G, and 2G) also increased in intensity and became more well-defined. The integrated intensity ratios of D and G bands (ID/IG) increase as the size of the GQDs approaches 2 nm and rapidly decrease for larger graphene structures. We present a quantitative comparison of ID/IG ratios for the GQDs and for defects introduced into large area graphenes through ion bombardment, for which inter-defect distances are comparable to the sizes of GQDs studied here. Close agreement suggests the ID/IG ratio as a size diagnostic for other nanographenes. Finally, we show that Raman spectroscopy is also a good diagnostic tool for monitoring the formation of bottom-up synthesized GQDs.
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Affiliation(s)
- Enkeleda Dervishi
- Materials Physics and Applications Division, Center for Integrated Nanotechnologies, Los Alamos, New Mexico 87545, USA.
| | - Zhiqiang Ji
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
| | - Han Htoon
- Materials Physics and Applications Division, Center for Integrated Nanotechnologies, Los Alamos, New Mexico 87545, USA.
| | - Milan Sykora
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
| | - Stephen K Doorn
- Materials Physics and Applications Division, Center for Integrated Nanotechnologies, Los Alamos, New Mexico 87545, USA.
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14
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He X, Htoon H, Doorn SK, Pernice WHP, Pyatkov F, Krupke R, Jeantet A, Chassagneux Y, Voisin C. Author Correction: Carbon nanotubes as emerging quantum-light sources. Nat Mater 2019; 18:770. [PMID: 31118489 DOI: 10.1038/s41563-019-0406-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Affiliation(s)
- X He
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - H Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - S K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - W H P Pernice
- Institute of Physics, University of Münster, Münster, Germany
| | - F Pyatkov
- Institute of Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe, Germany
- Institute of Materials Science, Technische Universität Darmstadt, Darmstadt, Germany
| | - R Krupke
- Institute of Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe, Germany
- Institute of Materials Science, Technische Universität Darmstadt, Darmstadt, Germany
| | - A Jeantet
- Laboratoire Pierre Aigrain, École Normale Supérieure, PSL University, Université Paris Diderot, Sorbonne Paris Cité, Sorbonne Université, CNRS, Paris, France
| | - Y Chassagneux
- Laboratoire Pierre Aigrain, École Normale Supérieure, PSL University, Université Paris Diderot, Sorbonne Paris Cité, Sorbonne Université, CNRS, Paris, France
| | - C Voisin
- Laboratoire Pierre Aigrain, École Normale Supérieure, PSL University, Université Paris Diderot, Sorbonne Paris Cité, Sorbonne Université, CNRS, Paris, France.
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15
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He X, Sun L, Gifford BJ, Tretiak S, Piryatinski A, Li X, Htoon H, Doorn SK. Intrinsic limits of defect-state photoluminescence dynamics in functionalized carbon nanotubes. Nanoscale 2019; 11:9125-9132. [PMID: 31032824 DOI: 10.1039/c9nr02175b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Defect states introduced to single wall carbon nanotubes (SWCNTs) by covalent functionalization give rise to novel photophysics and are showing promise as sources of room-temperature quantum emission of interest for quantum information technologies. Evaluation of their ultimate potential for such needs requires a knowledge of intrinsic dynamic and coherence behaviors. Here we probe population relaxation and dephasing time (T1 and T2, respectively) of defect states following deposition of functionalized SWCNTs on polystyrene substrates that are subjected to an isopropanol rinse to remove surfactant. Low-temperature (4 K) photo-luminescence linewidths (∼100 μeV) following surfactant removal are a factor of ten narrower than those for unrinsed SWCNTs. Measured recombination lifetimes, on the order of 1.5 ns, compare well with those estimated from DFT calculations, indicating that the intrinsic radiatively-limited lifetime is approached following this sample treatment. Dephasing times evaluated directly through an interferometric approach compare closely to those established by photoluminescence linewidths. Dephasing times as high as 12 ps are found; a factor of up to 6 times greater than those evaluated for band-edge exciton states. Such enhancement of dephasing and photoluminescence lifetime behavior is a direct consequence of exciton localization at the SWCNT defect sites.
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Affiliation(s)
- Xiaowei He
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
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16
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Kim Y, Velizhanin KA, He X, Sarpkaya I, Yomogida Y, Tanaka T, Kataura H, Doorn SK, Htoon H. Photoluminescence Intensity Fluctuations and Temperature-Dependent Decay Dynamics of Individual Carbon Nanotube sp 3 Defects. J Phys Chem Lett 2019; 10:1423-1430. [PMID: 30848914 DOI: 10.1021/acs.jpclett.8b03732] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Recent demonstration of room temperature, telecommunication wavelength single photon generation by sp3 defects of single wall carbon nanotubes established these defects as a new class of quantum materials. However, their practical utilization in development of quantum light sources calls for a significant improvement in their imperfect quantum yield (QY∼10-30%). PL intensity fluctuations observed with some defects also need to be eliminated. Aiming toward attaining fundamental understanding necessary for addressing these critical issues, we investigate PL intensity fluctuation and PL decay dynamics of aryl sp3 defects of (6,5), (7,5), and (10,3) single wall carbon nanotubes (SWCNTs) at temperatures ranging from 300 to 4 K. By correlating defect-state PL intensity fluctuations with change (or lack of change) in PL decay dynamics, we identified random variations in the trapping efficiency of E11 band-edge excitons (likely resulting from the existence of a fluctuating potential barrier in the vicinity of the defect) as the mechanism mainly responsible for the defect PL intensity fluctuations. Furthermore, by analyzing the temperature dependence of PL intensity and decay dynamics of individual defects based on a kinetic model involving the trapping and detrapping of excitons by optically allowed and forbidden (bright and dark) defect states, we estimate the height of the potential barrier to be in the 3-22 meV range. Our analysis also provides further confirmation of recent DFT simulation results that the emissive sp3 defect state is accompanied by an energetically higher-lying optically forbidden (dark) exciton state.
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Affiliation(s)
- Younghee Kim
- Center for Integrated Nanotechnologies, Materials Physics and Application Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Kirill A Velizhanin
- Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Xiaowei He
- Center for Integrated Nanotechnologies, Materials Physics and Application Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Ibrahim Sarpkaya
- Center for Integrated Nanotechnologies, Materials Physics and Application Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Yohei Yomogida
- Nanomaterials Research Institute , National Institute of Advanced Industrial Science and Technology (AIST) , Tsukuba , Ibaraki 305-8565 , Japan
| | - Takeshi Tanaka
- Nanomaterials Research Institute , National Institute of Advanced Industrial Science and Technology (AIST) , Tsukuba , Ibaraki 305-8565 , Japan
| | - Hiromichi Kataura
- Nanomaterials Research Institute , National Institute of Advanced Industrial Science and Technology (AIST) , Tsukuba , Ibaraki 305-8565 , Japan
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Application Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Application Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
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17
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Ji Z, Dervishi E, Doorn SK, Sykora M. Size-Dependent Electronic Properties of Uniform Ensembles of Strongly Confined Graphene Quantum Dots. J Phys Chem Lett 2019; 10:953-959. [PMID: 30764609 DOI: 10.1021/acs.jpclett.9b00119] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The electronic structure of a series of bottom-up synthesized graphene quantum dots (GQDs) smaller than 2 nm was investigated by spectroelectrochemistry, yielding insights not previously available from ensemble-level studies. The results show that for the strongly confined GQDs the dependence of the band gap on the GQD size deviates from the prediction of the standard Dirac Fermion model but agrees well with the models explicitly accounting for the electron-electron and electron-hole interactions. The HOMO/LUMO energy levels are found to be distributed nearly symmetrically around the 0 V value versus normal hydrogen electrode (NHE), becoming more positive/negative, respectively, with increasing GQD size. The exciton binding energies are found to follow power dependence on the number of carbon atoms per GQD, with the experimental values falling within the range of ∼0.1 to ∼0.6 eV. Given the broad accessibility of the described experimental tools and methods, our work opens a path to a more systematic examination of quantum confinement effects in GQDs.
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Affiliation(s)
- Zhiqiang Ji
- Chemistry Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Enkeleda Dervishi
- Materials Physics and Applications Division, Center for Integrated Nanotechnologies , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Stephen K Doorn
- Materials Physics and Applications Division, Center for Integrated Nanotechnologies , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Milan Sykora
- Chemistry Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
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18
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Liu S, Vaskin A, Addamane S, Leung B, Tsai MC, Yang Y, Vabishchevich PP, Keeler GA, Wang G, He X, Kim Y, Hartmann NF, Htoon H, Doorn SK, Zilk M, Pertsch T, Balakrishnan G, Sinclair MB, Staude I, Brener I. Light-Emitting Metasurfaces: Simultaneous Control of Spontaneous Emission and Far-Field Radiation. Nano Lett 2018; 18:6906-6914. [PMID: 30339762 DOI: 10.1021/acs.nanolett.8b02808] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Light-emitting sources and devices permeate every aspect of our lives and are used in lighting, communications, transportation, computing, and medicine. Advances in multifunctional and "smart lighting" would require revolutionary concepts in the control of emission spectra and directionality. Such control might be possible with new schemes and regimes of light-matter interaction paired with developments in light-emitting materials. Here we show that all-dielectric metasurfaces made from III-V semiconductors with embedded emitters have the potential to provide revolutionary lighting concepts and devices, with new functionality that goes far beyond what is available in existing technologies. Specifically, we use Mie-resonant metasurfaces made from semiconductor heterostructures containing epitaxial quantum dots. By controlling the symmetry of the resonant modes, their overlap with the emission spectra, and other structural parameters, we can enhance the brightness by 2 orders of magnitude, as well as reduce its far-field divergence significantly.
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Affiliation(s)
- Sheng Liu
- Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
- Center for Integrated Nanotechnologies , Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
| | - Aleksandr Vaskin
- Institute of Applied Physics, Abbe Center of Photonics , Friedrich Schiller University Jena , 07745 Jena , Germany
| | - Sadhvikas Addamane
- Center for High Technology Materials (CHTM), University of New Mexico , Albuquerque , New Mexico United States
| | - Benjamin Leung
- Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
| | - Miao-Chan Tsai
- Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
| | - Yuanmu Yang
- Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
| | - Polina P Vabishchevich
- Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
- Center for Integrated Nanotechnologies , Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
| | - Gordon A Keeler
- Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
| | - George Wang
- Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
| | - Xiaowei He
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Younghee Kim
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Nicolai F Hartmann
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Matthias Zilk
- Institute of Applied Physics, Abbe Center of Photonics , Friedrich Schiller University Jena , 07745 Jena , Germany
| | - Thomas Pertsch
- Institute of Applied Physics, Abbe Center of Photonics , Friedrich Schiller University Jena , 07745 Jena , Germany
| | - Ganesh Balakrishnan
- Center for High Technology Materials (CHTM), University of New Mexico , Albuquerque , New Mexico United States
| | - Michael B Sinclair
- Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
| | - Isabelle Staude
- Institute of Applied Physics, Abbe Center of Photonics , Friedrich Schiller University Jena , 07745 Jena , Germany
| | - Igal Brener
- Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
- Center for Integrated Nanotechnologies , Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
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19
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He X, Htoon H, Doorn SK, Pernice WHP, Pyatkov F, Krupke R, Jeantet A, Chassagneux Y, Voisin C. Publisher Correction: Carbon nanotubes as emerging quantum-light sources. Nat Mater 2018; 17:843. [PMID: 29995875 DOI: 10.1038/s41563-018-0141-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In the version of this Perspective originally published, the x-axis label of Fig. 1d was missing; it should have read 'Wavelength (nm)'. The units of the y axis of Fig. 3b were incorrect; they should have been meV. And the citation of Fig. 3c in the main text was incorrect; it should have been to Fig. 3b. These issues have now been corrected.
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Affiliation(s)
- X He
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - H Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - S K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - W H P Pernice
- Institute of Physics, University of Münster, Münster, Germany
| | - F Pyatkov
- Institute of Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe, Germany
- Institute of Materials Science, Technische Universität Darmstadt, Darmstadt, Germany
| | - R Krupke
- Institute of Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe, Germany
- Institute of Materials Science, Technische Universität Darmstadt, Darmstadt, Germany
| | - A Jeantet
- Laboratoire Pierre Aigrain, École Normale Supérieure, PSL University, Université Paris Diderot, Sorbonne Paris Cité, Sorbonne Université, CNRS, Paris, France
| | - Y Chassagneux
- Laboratoire Pierre Aigrain, École Normale Supérieure, PSL University, Université Paris Diderot, Sorbonne Paris Cité, Sorbonne Université, CNRS, Paris, France
| | - C Voisin
- Laboratoire Pierre Aigrain, École Normale Supérieure, PSL University, Université Paris Diderot, Sorbonne Paris Cité, Sorbonne Université, CNRS, Paris, France.
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20
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He X, Velizhanin KA, Bullard G, Bai Y, Olivier JH, Hartmann NF, Gifford BJ, Kilina S, Tretiak S, Htoon H, Therien MJ, Doorn SK. Solvent- and Wavelength-Dependent Photoluminescence Relaxation Dynamics of Carbon Nanotube sp 3 Defect States. ACS Nano 2018; 12:8060-8070. [PMID: 29995379 DOI: 10.1021/acsnano.8b02909] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Photoluminescent sp3 defect states introduced to single wall carbon nanotubes (SWCNTs) through low-level covalent functionalization create new photophysical behaviors and functionality as a result of defect sites acting as exciton traps. Evaluation of relaxation dynamics in varying dielectric environments can aid in advancing a more complete description of defect-state relaxation pathways and electronic structure. Here, we exploit helical wrapping polymers as a route to suspending (6,5) SWCNTs covalently functionalized with 4-methoxybenzene in solvent systems including H2O, D2O, methanol, dimethylformamide, tetrahydrofuran, and toluene, spanning a range of dielectric constants from 80 to 3. Defect-state photoluminescence decays were measured as a function of emission wavelength and solvent environment. Emission decays are biexponential, with short lifetime components on the order of 65 ps and long components ranging from around 100 to 350 ps. Both short and long decay components increase as emission wavelength increases, while only the long lifetime component shows a solvent dependence. We demonstrate that the wavelength dependence is a consequence of thermal detrapping of defect-state excitons to produce mobile E11 excitons, providing an important mechanism for loss of defect-state population. Deeper trap states (i.e., those emitting at longer wavelengths) result in a decreased rate for thermal loss. The solvent-independent behavior of the short lifetime component is consistent with its assignment as the characteristic time for redistribution of exciton population between bright and dark defect states. The solvent dependence of the long lifetime component is shown to be consistent with relaxation via an electronic to vibrational energy transfer mechanism, in which energy is resonantly lost to solvent vibrations in a complementary mechanism to multiphonon decay processes.
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Affiliation(s)
- Xiaowei He
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Kirill A Velizhanin
- Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - George Bullard
- Department of Chemistry, French Family Science Center , Duke University , Durham , North Carolina 27708 , United States
| | - Yusong Bai
- Department of Chemistry, French Family Science Center , Duke University , Durham , North Carolina 27708 , United States
| | - Jean-Hubert Olivier
- Department of Chemistry, French Family Science Center , Duke University , Durham , North Carolina 27708 , United States
| | - Nicolai F Hartmann
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Brendan J Gifford
- Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
- Center for Nonlinear Sciences , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
- Department of Chemistry and Biochemistry , North Dakota State University , Fargo , North Dakota 58108 , United States
| | - Svetlana Kilina
- Department of Chemistry and Biochemistry , North Dakota State University , Fargo , North Dakota 58108 , United States
| | - Sergei Tretiak
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
- Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Michael J Therien
- Department of Chemistry, French Family Science Center , Duke University , Durham , North Carolina 27708 , United States
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
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21
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He X, Htoon H, Doorn SK, Pernice WHP, Pyatkov F, Krupke R, Jeantet A, Chassagneux Y, Voisin C. Carbon nanotubes as emerging quantum-light sources. Nat Mater 2018; 17:663-670. [PMID: 29915427 DOI: 10.1038/s41563-018-0109-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 05/14/2018] [Indexed: 05/18/2023]
Abstract
Progress in quantum computing and quantum cryptography requires efficient, electrically triggered, single-photon sources at room temperature in the telecom wavelengths. It has been long known that semiconducting single-wall carbon nanotubes (SWCNTs) display strong excitonic binding and emit light over a broad range of wavelengths, but their use has been hampered by a low quantum yield and a high sensitivity to spectral diffusion and blinking. In this Perspective, we discuss recent advances in the mastering of SWCNT optical properties by chemistry, electrical contacting and resonator coupling towards advancing their use as quantum light sources. We describe the latest results in terms of single-photon purity, generation efficiency and indistinguishability. Finally, we consider the main fundamental challenges stemming from the unique properties of SWCNTs and the most promising roads for SWCNT-based chip integrated quantum photonic sources.
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Affiliation(s)
- X He
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - H Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - S K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - W H P Pernice
- Institute of Physics, University of Münster, Münster, Germany
| | - F Pyatkov
- Institute of Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe, Germany
- Institute of Materials Science, Technische Universität Darmstadt, Darmstadt, Germany
| | - R Krupke
- Institute of Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe, Germany
- Institute of Materials Science, Technische Universität Darmstadt, Darmstadt, Germany
| | - A Jeantet
- Laboratoire Pierre Aigrain, École Normale Supérieure, PSL University, Université Paris Diderot, Sorbonne Paris Cité, Sorbonne Université, CNRS, Paris, France
| | - Y Chassagneux
- Laboratoire Pierre Aigrain, École Normale Supérieure, PSL University, Université Paris Diderot, Sorbonne Paris Cité, Sorbonne Université, CNRS, Paris, France
| | - C Voisin
- Laboratoire Pierre Aigrain, École Normale Supérieure, PSL University, Université Paris Diderot, Sorbonne Paris Cité, Sorbonne Université, CNRS, Paris, France.
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22
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Shayan K, He X, Luo Y, Rabut C, Li X, Hartmann NF, Blackburn JL, Doorn SK, Htoon H, Strauf S. Suppression of exciton dephasing in sidewall-functionalized carbon nanotubes embedded into metallo-dielectric antennas. Nanoscale 2018; 10:12631-12638. [PMID: 29943788 DOI: 10.1039/c8nr03542c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Covalent functionalization of single-walled carbon nanotubes (SWCNTs) is a promising route to enhance the quantum yield of exciton emission and can lead to single-photon emission at room temperature. However, the spectral linewidth of the defect-related E11* emission remains rather broad. Here, we systematically investigate the low-temperature exciton emission of individual SWCNTs that have been dispersed with sodium-deoxycholate (DOC) and polyfluorene (PFO-BPy), are grown by laser vaporization (LV) or by CoMoCat techniques and are functionalized with oxygen as well as 3,5-dichlorobenzene groups. The E11 excitons in oxygen-functionalized SWCNTs remain rather broad with up to 10 meV linewidth while exciton emission from 3,5-dichlorobenzene functionalized SWCNTs is found to be about one order of magnitude narrower. In all cases, wrapping with PFO-BPy provides significantly better protection against pump induced dephasing compared to DOC. To further study the influence of exciton localization on pump-induced dephasing, we have embedded the functionalized SWCNTs into metallo-dielectric antenna cavities to maximize light collection. We show that 0D excitons attributed to the E11* emission of 3,5-dichlorobenzene quantum defects of LV-grown SWCNTs can display near resolution-limited linewidths down to 35 μeV. Interestingly, these 0D excitons give rise to a 3-fold suppressed pump-induced exciton dephasing compared to the E11 excitons in the same SWCNT. These findings provide a foundation to build a unified description of the emergence of novel optical behavior from the interplay of covalently introduced defects, dispersants, and exciton confinement in SWCNTs and might further lead to the realization of indistinguishable photons from carbon nanotubes.
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Affiliation(s)
- Kamran Shayan
- Department of Physics, Stevens Institute of Technology, Hoboken, NJ 07030, USA.
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23
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Danné N, Kim M, Godin AG, Kwon H, Gao Z, Wu X, Hartmann NF, Doorn SK, Lounis B, Wang Y, Cognet L. Ultrashort Carbon Nanotubes That Fluoresce Brightly in the Near-Infrared. ACS Nano 2018; 12:6059-6065. [PMID: 29889499 DOI: 10.1021/acsnano.8b02307] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The intrinsic near-infrared photoluminescence observed in long single-walled carbon nanotubes is known to be quenched in ultrashort nanotubes due to their tiny size as compared to the exciton diffusion length in these materials (>100 nm). Here, we show that intense photoluminescence can be created in ultrashort nanotubes (∼40 nm length) upon incorporation of exciton-trapping sp3 defect sites. Using super-resolution photoluminescence imaging at <25 nm resolution, we directly show the preferential localization of excitons at the nanotube ends, which separate by less than 40 nm and behave as independent emitters. This unexpected observation opens the possibility to synthesize fluorescent ultrashort nanotubes-a goal that has been long thought impossible-for bioimaging applications, where bright near-infrared photoluminescence and small size are highly desirable, and for quantum information science, where high quality and well-controlled near-infrared single photon emitters are needed.
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Affiliation(s)
- Noémie Danné
- Laboratoire Photonique Numérique et Nanosciences , Univ. Bordeaux , UMR 5298, F-33400 Talence , France
- Institut d'Optique & CNRS , LP2N UMR 5298, F-33400 Talence , France
| | - Mijin Kim
- Department of Chemistry and Biochemistry , University of Maryland , College Park , Maryland 20742 , United States
| | - Antoine G Godin
- Laboratoire Photonique Numérique et Nanosciences , Univ. Bordeaux , UMR 5298, F-33400 Talence , France
- Institut d'Optique & CNRS , LP2N UMR 5298, F-33400 Talence , France
| | - Hyejin Kwon
- Department of Chemistry and Biochemistry , University of Maryland , College Park , Maryland 20742 , United States
| | - Zhenghong Gao
- Laboratoire Photonique Numérique et Nanosciences , Univ. Bordeaux , UMR 5298, F-33400 Talence , France
- Institut d'Optique & CNRS , LP2N UMR 5298, F-33400 Talence , France
| | - Xiaojian Wu
- Department of Chemistry and Biochemistry , University of Maryland , College Park , Maryland 20742 , United States
| | - Nicolai F Hartmann
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 United States
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 United States
| | - Brahim Lounis
- Laboratoire Photonique Numérique et Nanosciences , Univ. Bordeaux , UMR 5298, F-33400 Talence , France
- Institut d'Optique & CNRS , LP2N UMR 5298, F-33400 Talence , France
| | - YuHuang Wang
- Department of Chemistry and Biochemistry , University of Maryland , College Park , Maryland 20742 , United States
- Maryland NanoCenter , University of Maryland , College Park , Maryland 20742 , United States
| | - Laurent Cognet
- Laboratoire Photonique Numérique et Nanosciences , Univ. Bordeaux , UMR 5298, F-33400 Talence , France
- Institut d'Optique & CNRS , LP2N UMR 5298, F-33400 Talence , France
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24
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Ishii A, He X, Hartmann NF, Machiya H, Htoon H, Doorn SK, Kato YK. Enhanced Single-Photon Emission from Carbon-Nanotube Dopant States Coupled to Silicon Microcavities. Nano Lett 2018; 18:3873-3878. [PMID: 29781621 DOI: 10.1021/acs.nanolett.8b01170] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Single-walled carbon nanotubes are a promising material as quantum light sources at room temperature and as nanoscale light sources for integrated photonic circuits on silicon. Here, we show that the integration of dopant states in carbon nanotubes and silicon microcavities can provide bright and high-purity single-photon emitters on a silicon photonics platform at room temperature. We perform photoluminescence spectroscopy and observe the enhancement of emission from the dopant states by a factor of ∼50, and cavity-enhanced radiative decay is confirmed using time-resolved measurements, in which a ∼30% decrease of emission lifetime is observed. The statistics of photons emitted from the cavity-coupled dopant states are investigated by photon-correlation measurements, and high-purity single photon generation is observed. The excitation power dependence of photon emission statistics shows that the degree of photon antibunching can be kept high even when the excitation power increases, while the single-photon emission rate can be increased to ∼1.7 × 107 Hz.
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Affiliation(s)
- Akihiro Ishii
- Nanoscale Quantum Photonics Laboratory, RIKEN , Saitama 351-0198 , Japan
- Quantum Optoelectronics Research Team, RIKEN Center for Advanced Photonics , Saitama 351-0198 , Japan
| | - Xiaowei He
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Nicolai F Hartmann
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Hidenori Machiya
- Nanoscale Quantum Photonics Laboratory, RIKEN , Saitama 351-0198 , Japan
- Department of Electrical Engineering , The University of Tokyo , Tokyo 113-8656 , Japan
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Yuichiro K Kato
- Nanoscale Quantum Photonics Laboratory, RIKEN , Saitama 351-0198 , Japan
- Quantum Optoelectronics Research Team, RIKEN Center for Advanced Photonics , Saitama 351-0198 , Japan
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25
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Gifford BJ, Sifain AE, Htoon H, Doorn SK, Kilina S, Tretiak S. Correction Scheme for Comparison of Computed and Experimental Optical Transition Energies in Functionalized Single-Walled Carbon Nanotubes. J Phys Chem Lett 2018; 9:2460-2468. [PMID: 29678108 DOI: 10.1021/acs.jpclett.8b00653] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Covalent functionalization of single-walled carbon nanotubes (SWCNTs) introduces red-shifted emission features in the near-infrared spectral range due to exciton localization around the defect site. Such chemical modifications increase their potential use as near-infrared emitters and single-photon sources in telecommunications applications. Density functional theory (DFT) studies using finite-length tube models have been used to calculate their optical transition energies. Predicted energies are typically blue-shifted compared to experiment due to methodology errors including imprecise self-interaction corrections in the density functional and finite-size basis sets. Furthermore, artificial quantum confinement in finite models cannot be corrected by a constant-energy shift since they depend on the degree of exciton localization. Herein, we present a method that corrects the emission energies predicted by time-dependent DFT. Confinement and methodology errors are separately estimated using experimental data for unmodified tubes. Corrected emission energies are in remarkable agreement with experiment, suggesting the value of this straightforward method toward predicting and interpreting the optical features of functionalized SWCNTs.
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Affiliation(s)
- Brendan J Gifford
- Department of Chemistry and Biochemistry , North Dakota State University , Fargo , North Dakota 58108 , United States
| | - Andrew E Sifain
- Department of Physics and Astronomy , University of Southern California , Los Angeles , California 90089 , United States
| | | | | | - Svetlana Kilina
- Department of Chemistry and Biochemistry , North Dakota State University , Fargo , North Dakota 58108 , United States
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26
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Simpson JR, Roslyak O, Duque JG, Hároz EH, Crochet JJ, Telg H, Piryatinski A, Walker ARH, Doorn SK. Resonance Raman signature of intertube excitons in compositionally-defined carbon nanotube bundles. Nat Commun 2018; 9:637. [PMID: 29434198 PMCID: PMC5809379 DOI: 10.1038/s41467-018-03057-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 01/17/2018] [Indexed: 11/23/2022] Open
Abstract
Electronic interactions in low-dimensional nanomaterial heterostructures can lead to novel optical responses arising from exciton delocalization over the constituent materials. Similar phenomena have been suggested to arise between closely interacting semiconducting carbon nanotubes of identical structure. Such behavior in carbon nanotubes has potential to generate new exciton physics, impact exciton transport mechanisms in nanotube networks, and place nanotubes as one-dimensional models for such behaviors in systems of higher dimensionality. Here we use resonance Raman spectroscopy to probe intertube interactions in (6,5) chirality-enriched bundles. Raman excitation profiles for the radial breathing mode and G-mode display a previously unobserved sharp resonance feature. We show the feature is evidence for creation of intertube excitons and is identified as a Fano resonance arising from the interaction between intratube and intertube excitons. The universality of the model suggests that similar Raman excitation profile features may be observed for interlayer exciton resonances in 2D multilayered systems. Bundles of single-wall carbon nanotubes with enriched chirality can be used as model systems for exploring exciton physics in low-dimensional nanostructures. Here, the authors use resonant Raman spectroscopy to probe intertube interactions in bundles of (6,5)-enriched carbon nanotubes, and observe a Fano resonance arising from coupling between intertube and intratube excitons.
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Affiliation(s)
- Jeffrey R Simpson
- Engineering Physics Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD, 20899, USA.,Department of Physics, Astronomy, and Geosciences, Towson University, Towson, MD, 21252, USA
| | - Oleksiy Roslyak
- Physics and Engineering Physics, Fordham University, Bronx, NY, 10458, USA
| | - Juan G Duque
- Chemistry Division, Physical Chemistry and Applied Spectroscopy, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Erik H Hároz
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Jared J Crochet
- Chemistry Division, Physical Chemistry and Applied Spectroscopy, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Hagen Telg
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Andrei Piryatinski
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
| | - Angela R Hight Walker
- Engineering Physics Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD, 20899, USA.
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
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27
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He X, Gifford BJ, Hartmann NF, Ihly R, Ma X, Kilina SV, Luo Y, Shayan K, Strauf S, Blackburn JL, Tretiak S, Doorn SK, Htoon H. Low-Temperature Single Carbon Nanotube Spectroscopy of sp 3 Quantum Defects. ACS Nano 2017; 11:10785-10796. [PMID: 28958146 DOI: 10.1021/acsnano.7b03022] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Aiming to unravel the relationship between chemical configuration and electronic structure of sp3 defects of aryl-functionalized (6,5) single-walled carbon nanotubes (SWCNTs), we perform low-temperature single nanotube photoluminescence (PL) spectroscopy studies and correlate our observations with quantum chemistry simulations. We observe sharp emission peaks from individual defect sites that are spread over an extremely broad, 1000-1350 nm, spectral range. Our simulations allow us to attribute this spectral diversity to the occurrence of six chemically and energetically distinct defect states resulting from topological variation in the chemical binding configuration of the monovalent aryl groups. Both PL emission efficiency and spectral line width of the defect states are strongly influenced by the local dielectric environment. Wrapping the SWCNT with a polyfluorene polymer provides the best isolation from the environment and yields the brightest emission with near-resolution limited spectral line width of 270 μeV, as well as spectrally resolved emission wings associated with localized acoustic phonons. Pump-dependent studies further revealed that the defect states are capable of emitting single, sharp, isolated PL peaks over 3 orders of magnitude increase in pump power, a key characteristic of two-level systems and an important prerequisite for single-photon emission with high purity. These findings point to the tremendous potential of sp3 defects in development of room temperature quantum light sources capable of operating at telecommunication wavelengths as the emission of the defect states can readily be extended to this range via use of larger diameter SWCNTs.
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Affiliation(s)
| | - Brendan J Gifford
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108, United States
| | | | - Rachelle Ihly
- Chemical and Materials Science Center, National Renewable Energy Laboratory , 1617 Cole Boulevard, Golden, Colorado 80401, United States
| | | | - Svetlana V Kilina
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108, United States
| | - Yue Luo
- Department of Physics, Stevens Institute of Technology , Hoboken, New Jersey 07030, United States
| | - Kamran Shayan
- Department of Physics, Stevens Institute of Technology , Hoboken, New Jersey 07030, United States
| | - Stefan Strauf
- Department of Physics, Stevens Institute of Technology , Hoboken, New Jersey 07030, United States
| | - Jeffrey L Blackburn
- Chemical and Materials Science Center, National Renewable Energy Laboratory , 1617 Cole Boulevard, Golden, Colorado 80401, United States
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28
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Ma X, Hartmann NF, Velizhanin KA, Baldwin JKS, Adamska L, Tretiak S, Doorn SK, Htoon H. Multi-exciton emission from solitary dopant states of carbon nanotubes. Nanoscale 2017; 9:16143-16148. [PMID: 29053165 DOI: 10.1039/c7nr06661a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
By separating the photons from slow and fast decays of single and multi-exciton states in a time gated 2nd order photon correlation experiment, we show that solitary oxygen dopant states of single-walled carbon nanotubes (SWCNTs) allow emission of photon pairs with efficiencies as high as 44% of single exciton emission. Our pump dependent time resolved photoluminescence (PL) studies further reveal diffusion-limited exciton-exciton annihilation as the key process that limits the emission of multi-excitons at high pump fluences. We further postulate that creation of additional permanent exciton quenching sites occurring under intense laser irradiation leads to permanent PL quenching. With this work, we bring out multi-excitonic processes of solitary dopant states as a new area to be explored for potential applications in lasing and entangled photon generation.
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Affiliation(s)
- Xuedan Ma
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, New Mexico 87545, USA.
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29
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Ma X, James AR, Hartmann NF, Baldwin JK, Dominguez J, Sinclair MB, Luk TS, Wolf O, Liu S, Doorn SK, Htoon H, Brener I. Solitary Oxygen Dopant Emission from Carbon Nanotubes Modified by Dielectric Metasurfaces. ACS Nano 2017; 11:6431-6439. [PMID: 28535349 DOI: 10.1021/acsnano.7b02951] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
All-dielectric metasurfaces made from arrays of high index nanoresonators supporting strong magnetic dipole modes have emerged as a low-loss alternative to plasmonic metasurfaces. Here we use oxygen-doped single-walled carbon nanotubes (SWCNTs) as quantum emitters and couple them to silicon metasurfaces to study effects of the magnetic dipole modes of the constituent nanoresonators on the photoluminescence (PL) of individual SWCNTs. We find that when in resonance, the magnetic mode of the silicon nanoresonators can lead to a moderate average PL enhancement of 0.8-4.0 of the SWCNTs, accompanied by an average increase in the radiative decay rate by a factor of 1.5-3.0. More interestingly, single dopant polarization experiments show an anomalous photoluminescence polarization rotation by coupling individual SWCNTs to silicon nanoresonators. Numerical simulations indicate that this is caused by modification of near-field polarization distribution at certain areas in the proximity of the silicon nanoresonators at the excitation wavelength, thus presenting an approach to control emission polarization. These findings indicate silicon nanoresonators as potential building blocks of quantum photonic circuits capable of manipulating PL intensity and polarization of single photon sources.
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Affiliation(s)
- Xuedan Ma
- Center for Integrated Nanotechnologies, Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
- Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
| | - Anthony R James
- Center for Integrated Nanotechnologies, Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
| | - Nicolai F Hartmann
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - Jon K Baldwin
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - Jason Dominguez
- Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
| | - Michael B Sinclair
- Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
| | - Ting S Luk
- Center for Integrated Nanotechnologies, Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
- Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
| | - Omri Wolf
- Center for Integrated Nanotechnologies, Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
- Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
| | - Sheng Liu
- Center for Integrated Nanotechnologies, Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
- Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - Igal Brener
- Center for Integrated Nanotechnologies, Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
- Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
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30
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Ma X, Cambré S, Wenseleers W, Doorn SK, Htoon H. Quasiphase Transition in a Single File of Water Molecules Encapsulated in (6,5) Carbon Nanotubes Observed by Temperature-Dependent Photoluminescence Spectroscopy. Phys Rev Lett 2017; 118:027402. [PMID: 28128601 DOI: 10.1103/physrevlett.118.027402] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Indexed: 05/14/2023]
Abstract
Molecules confined inside single-walled carbon nanotubes (SWCNTs) behave quite differently from their bulk analogues. In this Letter we present temperature-dependent (4.2 K up to room temperature) photoluminescence (PL) spectra of water-filled and empty single-chirality (6,5) SWCNTs. Superimposed on a linear temperature-dependent PL spectral shift of the empty SWCNTs, an additional stepwise PL spectral shift of the water-filled SWCNTs is observed at ∼150 K. With the empty SWCNTs serving as an ideal reference system, we assign this shift to temperature-induced changes occurring in the single-file chain of water molecules encapsulated in the tubes. Our molecular dynamics simulations further support the occurrence of a quasiphase transition of the orientational order of the water dipoles in the single-file chain.
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Affiliation(s)
- Xuedan Ma
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, New Mexico 87545, USA
| | - Sofie Cambré
- Experimental Condensed Matter Physics Laboratory, University of Antwerp, B-2610 Antwerp, Belgium
| | - Wim Wenseleers
- Experimental Condensed Matter Physics Laboratory, University of Antwerp, B-2610 Antwerp, Belgium
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, New Mexico 87545, USA
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, New Mexico 87545, USA
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31
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Mallajosyula AT, Nie W, Gupta G, Blackburn JL, Doorn SK, Mohite AD. Critical Role of the Sorting Polymer in Carbon Nanotube-Based Minority Carrier Devices. ACS Nano 2016; 10:10808-10815. [PMID: 27966903 DOI: 10.1021/acsnano.6b04885] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A prerequisite for carbon nanotube-based optoelectronic devices is the ability to sort them into a pure semiconductor phase. One of the most common sorting routes is enabled through using specific wrapping polymers. Here we show that subtle changes in the polymer structure can have a dramatic influence on the figures of merit of a carbon nanotube-based photovoltaic device. By comparing two commonly used polyfluorenes (PFO and PFO-BPy) for wrapping (7,5) and (6,5) chirality SWCNTs, we demonstrate that they have contrasting effects on the device efficiency. We attribute this to the differences in their ability to efficiently transfer charge. Although PFO may act as an efficient interfacial layer at the anode, PFO-BPy, having the additional pyridine side groups, forms a high resistance layer degrading the device efficiency. By comparing PFO|C60 and C60-only devices, we found that presence of a PFO layer at low optical densities resulted in the increase of all three solar cell parameters, giving nearly an order of magnitude higher efficiency over that of C60-only devices. In addition, with a relatively higher contribution to photocurrent from the PFO-C60 interface, an open circuit voltage of 0.55 V was obtained for PFO-(7,5)-C60 devices. On the other hand, PFO-BPy does not affect the open circuit voltage but drastically reduces the short circuit current density. These results indicate that the charge transport properties and energy levels of the sorting polymers have to be taken into account to fully understand their effect on carbon nanotube-based solar cells.
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Affiliation(s)
- Arun T Mallajosyula
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - Wanyi Nie
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - Gautam Gupta
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - Jeffrey L Blackburn
- Chemical and Materials Science Center, National Renewable Energy Laboratory , 1617 Cole Boulevard, Golden, Colorado 80401, United States
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - Aditya D Mohite
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
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32
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Hartmann NF, Pramanik R, Dowgiallo AM, Ihly R, Blackburn JL, Doorn SK. Photoluminescence Imaging of Polyfluorene Surface Structures on Semiconducting Carbon Nanotubes: Implications for Thin Film Exciton Transport. ACS Nano 2016; 10:11449-11458. [PMID: 27936574 DOI: 10.1021/acsnano.6b07168] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Single-walled carbon nanotubes (SWCNTs) have potential to act as light-harvesting elements in thin film photovoltaic devices, but performance is in part limited by the efficiency of exciton diffusion processes within the films. Factors contributing to exciton transport can include film morphology encompassing nanotube orientation, connectivity, and interaction geometry. Such factors are often defined by nanotube surface structures that are not yet well understood. Here, we present the results of a combined pump-probe and photoluminescence imaging study of polyfluorene (PFO)-wrapped (6,5) and (7,5) SWCNTs that provide additional insight into the role played by polymer structures in defining exciton transport. Pump-probe measurements suggest exciton transport occurs over larger length scales in films composed of PFO-wrapped (7,5) SWCNTs, compared to those prepared from PFO-bpy-wrapped (6,5) SWCNTs. To explore the role the difference in polymer structure may play as a possible origin of differing transport behaviors, we performed a photoluminescence imaging study of individual polymer-wrapped (6,5) and (7,5) SWCNTs. The PFO-bpy-wrapped (6,5) SWCNTs showed more uniform intensity distributions along their lengths, in contrast to the PFO-wrapped (7,5) SWCNTs, which showed irregular, discontinuous intensity distributions. These differences likely originate from differences in surface coverage and suggest the PFO wrapping on (7,5) nanotubes produces a more open surface structure than is available with the PFO-bpy wrapping of (6,5) nanotubes. The open structure likely leads to improved intertube coupling that enhances exciton transport within the (7,5) films, consistent with the results of our pump-probe measurements.
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Affiliation(s)
- Nicolai F Hartmann
- Center for Integrated Nanotechnologies, MPA-CINT, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - Rajib Pramanik
- Center for Integrated Nanotechnologies, MPA-CINT, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | | | - Rachelle Ihly
- National Renewable Energy Laboratory , Golden, Colorado 80401, United States
| | - Jeffrey L Blackburn
- National Renewable Energy Laboratory , Golden, Colorado 80401, United States
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, MPA-CINT, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
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33
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Hartmann NF, Velizhanin KA, Haroz EH, Kim M, Ma X, Wang Y, Htoon H, Doorn SK. Photoluminescence Dynamics of Aryl sp(3) Defect States in Single-Walled Carbon Nanotubes. ACS Nano 2016; 10:8355-65. [PMID: 27529740 DOI: 10.1021/acsnano.6b02986] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Photoluminescent defect states introduced by sp(3) functionalization of semiconducting carbon nanotubes are rapidly emerging as important routes for boosting emission quantum yields and introducing new functionality. Knowledge of the relaxation dynamics of these states is required for understanding how functionalizing agents (molecular dopants) may be designed to access specific behaviors. We measure photoluminescence (PL) decay dynamics of sp(3) defect states introduced by aryl functionalization of the carbon nanotube surface. Results are given for five different nanotube chiralities, each doped with a range of aryl functionality. We find that the PL decays of these sp(3) defect states are biexponential, with both components relaxing on time scales of ∼100 ps. Exciton trapping at defects is found to increases PL lifetimes by a factor of 5-10, in comparison to those for the free exciton. A significant chirality dependence is observed in the decay times, ranging from 77 ps for (7,5) nanotubes to >600 ps for (5,4) structures. The strong correlation of time constants with emission energy indicates relaxation occurs via multiphonon decay processes, with close agreement to theoretical expectations. Variation of the aryl dopant further modulates decay times by 10-15%. The aryl defects also affect PL lifetimes of the free E11 exciton. Shortening of the E11 bright state lifetime as defect density increases provides further confirmation that defects act as exciton traps. A similar shortening of the E11 dark exciton lifetime is found as defect density increases, providing strong experimental evidence that dark excitons are also trapped at such defect sites.
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Affiliation(s)
| | | | | | - Mijin Kim
- Department of Chemistry and Biochemistry, University of Maryland , College Park, Maryland 20742, United States
| | | | - YuHuang Wang
- Department of Chemistry and Biochemistry, University of Maryland , College Park, Maryland 20742, United States
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34
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He X, Gao W, Xie L, Li B, Zhang Q, Lei S, Robinson JM, Hároz EH, Doorn SK, Wang W, Vajtai R, Ajayan PM, Adams WW, Hauge RH, Kono J. Wafer-scale monodomain films of spontaneously aligned single-walled carbon nanotubes. Nat Nanotechnol 2016; 11:633-8. [PMID: 27043199 DOI: 10.1038/nnano.2016.44] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 02/19/2016] [Indexed: 05/02/2023]
Abstract
The one-dimensional character of electrons, phonons and excitons in individual single-walled carbon nanotubes leads to extremely anisotropic electronic, thermal and optical properties. However, despite significant efforts to develop ways to produce large-scale architectures of aligned nanotubes, macroscopic manifestations of such properties remain limited. Here, we show that large (>cm(2)) monodomain films of aligned single-walled carbon nanotubes can be prepared using slow vacuum filtration. The produced films are globally aligned within ±1.5° (a nematic order parameter of ∼1) and are highly packed, containing 1 × 10(6) nanotubes in a cross-sectional area of 1 μm(2). The method works for nanotubes synthesized by various methods, and film thickness is controllable from a few nanometres to ∼100 nm. We use the approach to create ideal polarizers in the terahertz frequency range and, by combining the method with recently developed sorting techniques, highly aligned and chirality-enriched nanotube thin-film devices. Semiconductor-enriched devices exhibit polarized light emission and polarization-dependent photocurrent, as well as anisotropic conductivities and transistor action with high on/off ratios.
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Affiliation(s)
- Xiaowei He
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, USA
| | - Weilu Gao
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, USA
| | - Lijuan Xie
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Bo Li
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA
| | - Qi Zhang
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, USA
| | - Sidong Lei
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA
| | - John M Robinson
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, USA
| | - Erik H Hároz
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Weipeng Wang
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA
| | - Robert Vajtai
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA
| | - Pulickel M Ajayan
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA
| | - W Wade Adams
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA
| | - Robert H Hauge
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA
- Department of Chemistry, Rice University, Houston, Texas 77005, USA
| | - Junichiro Kono
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, USA
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA
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35
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Hartmann NF, Yalcin SE, Adamska L, Hároz EH, Ma X, Tretiak S, Htoon H, Doorn SK. Photoluminescence imaging of solitary dopant sites in covalently doped single-wall carbon nanotubes. Nanoscale 2015; 7:20521-20530. [PMID: 26586162 DOI: 10.1039/c5nr06343d] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Covalent dopants in semiconducting single wall carbon nanotubes (SWCNTs) are becoming important as routes for introducing new photoluminescent emitting states with potential for enhanced quantum yields, new functionality, and as species capable of near-IR room-temperature single photon emission. The origin and behavior of the dopant-induced emission is thus important to understand as a key requirement for successful room-T photonics and optoelectronics applications. Here, we use direct correlated two-color photoluminescence imaging to probe how the interplay between the SWCNT bright E(11) exciton and solitary dopant sites yields the dopant-induced emission for three different dopant species: oxygen, 4-methoxybenzene, and 4-bromobenzene. We introduce a route to control dopant functionalization to a low level as a means for introducing spatially well-separated solitary dopant sites. Resolution of emission from solitary dopant sites and correlation to their impact on E(11) emission allows confirmation of dopants as trapping sites for localization of E(11) excitons following their diffusive transport to the dopant site. Imaging of the dopant emission also reveals photoluminescence intermittency (blinking), with blinking dynamics being dependent on the specific dopant. Density functional theory calculations were performed to evaluate the stability of dopants and delineate the possible mechanisms of blinking. Theoretical modeling suggests that the trapping of free charges in the potential well created by permanent dipoles introduced by dopant atoms/groups is likely responsible for the blinking, with the strongest effects being predicted and observed for oxygen-doped SWCNTs.
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Affiliation(s)
- Nicolai F Hartmann
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
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36
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Abstract
The spatial extent of charged electronic states in semiconducting carbon nanotubes with indices (6,5) and (7,6) was evaluated using density functional theory. It was observed that electrons and holes self-trap along the nanotube axis on length scales of about 4 and 8 nm, respectively, which localize cations and anions on comparable length scales. Self-trapping is accompanied by local structural distortions showing periodic bond-length alternation. The average lengthening (shortening) of the bonds for anions (cations) is expected to shift the G-mode frequency to lower (higher) values. The smaller-diameter nanotube has reduced structural relaxation due to higher carbon-carbon bond strain. The reorganization energy due to charge-induced deformations in both nanotubes is found to be in the 30-60 meV range. Our results represent the first theoretical simulation of self-trapping of charge carriers in semiconducting nanotubes, and agree with available experimental data.
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Affiliation(s)
- Lyudmyla Adamska
- Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - George V Nazin
- Department of Chemistry and Biochemistry, University of Oregon , 1253 University of Oregon, Eugene, Oregon 97403, United States
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - Sergei Tretiak
- Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
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37
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Ma X, Hartmann NF, Baldwin JKS, Doorn SK, Htoon H. Room-temperature single-photon generation from solitary dopants of carbon nanotubes. Nat Nanotechnol 2015; 10:671-5. [PMID: 26167766 DOI: 10.1038/nnano.2015.136] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 06/02/2015] [Indexed: 05/23/2023]
Abstract
On-demand single-photon sources capable of operating at room temperature and the telecom wavelength range of 1,300-1,500 nm hold the key to the realization of novel technologies that span from sub-diffraction imaging to quantum key distribution and photonic quantum information processing. Here, we show that incorporation of undoped (6,5) single-walled carbon nanotubes into a SiO2 matrix can lead to the creation of solitary oxygen dopant states capable of fluctuation-free, room-temperature single-photon emission in the 1,100-1,300 nm wavelength range. We investigated the effects of temperature on photoluminescence emission efficiencies, fluctuations and decay dynamics of the dopant states and determined the conditions most suitable for the observation of single-photon emission. This emission can in principle be extended to 1,500 nm by doping of smaller-bandgap single-walled carbon nanotubes. This easy tunability presents a distinct advantage over existing defect centre single-photon emitters (for example, diamond defect centres). Our SiO2-encapsulated sample also presents exciting opportunities to apply Si/SiO2-based micro/nano-device fabrication techniques in the development of electrically driven single-photon sources and integration of these sources into quantum photonic devices and networks.
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Affiliation(s)
- Xuedan Ma
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Nicolai F Hartmann
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Jon K S Baldwin
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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38
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Ma X, Roslyak O, Duque JG, Pang X, Doorn SK, Piryatinski A, Dunlap DH, Htoon H. Influences of Exciton Diffusion and Exciton-Exciton Annihilation on Photon Emission Statistics of Carbon Nanotubes. Phys Rev Lett 2015; 115:017401. [PMID: 26182119 DOI: 10.1103/physrevlett.115.017401] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Indexed: 06/04/2023]
Abstract
Pump-dependent photoluminescence imaging and second-order photon correlation studies have been performed on individual single-walled carbon nanotubes (SWCNTs) at room temperature. These studies enable the extraction of both the exciton diffusion constant and the Auger recombination coefficient. A linear correlation between these parameters is attributed to the effect of environmental disorder in setting the exciton mean free path and capture-limited Auger recombination at this length scale. A suppression of photon antibunching is attributed to the creation of multiple spatially nonoverlapping excitons in SWCNTs, whose diffusion length is shorter than the laser spot size. We conclude that complete antibunching at room temperature requires an enhancement of the exciton-exciton annihilation rate that may become realizable in SWCNTs allowing for strong exciton localization.
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Affiliation(s)
- Xuedan Ma
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Oleskiy Roslyak
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
- Department of Physics and Engineering Physics, Fordham University, Bronx, New York 10458, USA
| | - Juan G Duque
- Physical Chemistry and Applied Spectroscopy, Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Xiaoying Pang
- High Power Electrodynamics, Accelerator Operations and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Stephen K Doorn
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Andrei Piryatinski
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - David H Dunlap
- Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - Han Htoon
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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39
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Fagan JA, Hároz EH, Ihly R, Gui H, Blackburn JL, Simpson JR, Lam S, Hight Walker AR, Doorn SK, Zheng M. Isolation of >1 nm Diameter Single-Wall Carbon Nanotube Species Using Aqueous Two-Phase Extraction. ACS Nano 2015; 9:5377-90. [PMID: 25871430 DOI: 10.1021/acsnano.5b01123] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
In this contribution we demonstrate the effective separation of single-wall carbon nanotube (SWCNT) species with diameters larger than 1 nm through multistage aqueous two-phase extraction (ATPE), including isolation at the near-monochiral species level up to at least the diameter range of SWCNTs synthesized by electric arc synthesis (1.3-1.6 nm). We also demonstrate that refined species are readily obtained from both the metallic and semiconducting subpopulations of SWCNTs and that this methodology is effective for multiple SWCNT raw materials. Using these data, we report an empirical function for the necessary surfactant concentrations in the ATPE method for separating different SWCNTs into either the lower or upper phase as a function of SWCNT diameter. This empirical correlation enables predictive separation design and identifies a subset of SWCNTs that behave unusually as compared to other species. These results not only dramatically increase the range of SWCNT diameters to which species selective separation can be achieved but also demonstrate that aqueous two-phase separations can be designed across experimentally accessible ranges of surfactant concentrations to controllably separate SWCNT populations of very small (∼0.62 nm) to very large diameters (>1.7 nm). Together, the results reported here indicate that total separation of all SWCNT species is likely feasible by the ATPE method, especially given future development of multistage automated extraction techniques.
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Affiliation(s)
| | - Erik H Hároz
- ‡Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Rachelle Ihly
- §National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Hui Gui
- ∥Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089, United States
| | - Jeffrey L Blackburn
- §National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | | | | | | | - Stephen K Doorn
- ‡Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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40
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Abstract
Polyclic aromatic hydrocarbons also called Graphene Molecules (GMs), with chemical composition C132H36(COOH)2 were synthesized in situ on the surface of transparent nanocrystalline indium tin oxide (nc-ITO) electrodes and their electronic structure was studied electrochemically and spectro-electrochemically. Variations in the potential applied onto the nc-ITO/GM electrodes induce only small changes in the observed current, but they produce dramatic changes in the absorption of the GMs, which are associated with their oxidation and reduction. Analysis of the absorption changes using a modified Nernst equation is used to determine standard potentials associated with the individual charge transfer processes. For the GMs prepared here, these were found to be E1,ox(0) = 0.77 ± 0.01 V and E2,ox(0) = 1.24 ± 0.02 V vs NHE for the first and second oxidation and E1,red(0) = -1.50 ± 0.04 V for the first reduction. The charge transfer processes are found to be nonideal. The nonideality factors associated with the oxidation and reduction processes are attributed to strong interactions between the GM redox centers. Under the conditions of potential cycling, GMs show rapid (seconds) color change with high contrast and stability. An electrochromic application is demonstrated wherein the GMs are used as the optically active component.
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Affiliation(s)
- Zhiqiang Ji
- †Chemistry Division, ‡Materials Physics, Applications Division, Center for Integrated Nano-Technologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Stephen K Doorn
- †Chemistry Division, ‡Materials Physics, Applications Division, Center for Integrated Nano-Technologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Milan Sykora
- †Chemistry Division, ‡Materials Physics, Applications Division, Center for Integrated Nano-Technologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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41
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Yalcin SE, Galande C, Kappera R, Yamaguchi H, Martinez U, Velizhanin KA, Doorn SK, Dattelbaum AM, Chhowalla M, Ajayan PM, Gupta G, Mohite AD. Direct imaging of charge transport in progressively reduced graphene oxide using electrostatic force microscopy. ACS Nano 2015; 9:2981-2988. [PMID: 25668323 DOI: 10.1021/nn507150q] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Graphene oxide (GO) has emerged as a multifunctional material that can be synthesized in bulk quantities and can be solution processed to form large-area atomic layered photoactive, flexible thin films for optoelectronic devices. This is largely due to the potential ability to tune electrical and optical properties of GO using functional groups. For the successful application of GO, it is key to understand the evolution of its optoelectronic properties as the GO undergoes a phase transition from its insulating and optically active state to the electrically conducting state with progressive reduction. In this paper, we use a combination of electrostatic force microscopy (EFM) and optical spectroscopy to monitor the emergence of the optoelectronic properties of GO with progressive reduction. EFM measurements enable, for the first time, direct visualization of charge propagation along the conducting pathways that emerge on progressively reduced graphene oxide (rGO) and demonstrate that with the increasing degree of reduction, injected charges can rapidly migrate over a distance of several micrometers, irrespective of their polarities. Direct imaging reveals the presence of an insurmountable potential barrier between reduced GO (rGO) and GO, which plays the decisive role in the charge transport. We complement charge imaging with theoretical modeling using quantum chemistry calculations that further demonstrate that the role of barrier in regulating the charge transport. Furthermore, by correlating the EFM measurements with photoluminescence imaging and electrical conductivity studies, we identify a bifunctional state in GO, where the optical properties are preserved along with good electrical conductivity, providing design principles for the development of GO-based, low-cost, thin-film optoelectronic applications.
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Affiliation(s)
- Sibel Ebru Yalcin
- †Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | | | | | - Hisato Yamaguchi
- ⊥MPA-11 Materials Synthesis and Integrated Devices, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Ulises Martinez
- ⊥MPA-11 Materials Synthesis and Integrated Devices, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Kirill A Velizhanin
- ∥T-1 Physics and Chemistry of Materials, Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Stephen K Doorn
- †Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Andrew M Dattelbaum
- ⊥MPA-11 Materials Synthesis and Integrated Devices, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | | | | | - Gautam Gupta
- ⊥MPA-11 Materials Synthesis and Integrated Devices, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Aditya D Mohite
- ⊥MPA-11 Materials Synthesis and Integrated Devices, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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42
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Liu J, Adamska L, Doorn SK, Tretiak S. Singlet and triplet excitons and charge polarons in cycloparaphenylenes: a density functional theory study. Phys Chem Chem Phys 2015; 17:14613-22. [DOI: 10.1039/c5cp01782c] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Upon excitation, electron–phonon coupling leads to spatial localization of the electronic wavefunction and distortion of molecular geometry.
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Affiliation(s)
- Jin Liu
- Department of Chemical Engineering
- University of Rochester
- Rochester
- USA
| | - Lyudmyla Adamska
- Theoretical Division (T-1) and Center for Nonlinear Studies (CNLS)
- Los Alamos National Laboratory
- Los Alamos
- USA
| | - Stephen K. Doorn
- Center for Integrated Nanotechnologies (CINT)
- Los Alamos National Laboratory
- Los Alamos
- USA
| | - Sergei Tretiak
- Theoretical Division (T-1) and Center for Nonlinear Studies (CNLS)
- Los Alamos National Laboratory
- Los Alamos
- USA
- Center for Integrated Nanotechnologies (CINT)
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43
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Ignatova T, Blades M, Duque JG, Doorn SK, Biaggio I, Rotkin SV. Formation and dynamics of "waterproof" photoluminescent complexes of rare earth ions in crowded environment. Phys Chem Chem Phys 2014; 16:26715-21. [PMID: 25379879 DOI: 10.1039/c4cp04342a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Understanding behavior of rare-earth ions (REI) in crowded environments is crucial for several nano- and bio-technological applications. Evolution of REI photoluminescence (PL) in small compartments inside a silica hydrogel, mimic to a soft matter bio-environment, has been studied and explained within a solvation model. The model uncovered the origin of high PL efficiency to be the formation of REI complexes, surrounded by bile salt (DOC) molecules. Comparative study of these REI-DOC complexes in bulk water solution and those enclosed inside the hydrogel revealed a strong correlation between an up to 5×-longer lifetime of REIs and appearance of the DOC ordered phase, further confirmed by dynamics of REI solvation shells, REI diffusion experiments and morphological characterization of microstructure of the hydrogel.
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Affiliation(s)
- Tetyana Ignatova
- Physics Department, Lehigh University, 16 Memorial Drive East, Bethlehem, PA 18020, USA
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44
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Ji Z, Wu R, Adamska L, Velizhanin KA, Doorn SK, Sykora M. In situ synthesis of graphene molecules on TiO2: application in sensitized solar cells. ACS Appl Mater Interfaces 2014; 6:20473-20478. [PMID: 25322280 DOI: 10.1021/am506047f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present a method for preparation of graphene molecules (GMs), whereby a polyphenylene precursor functionalized with surface anchoring groups, preadsorbed on surface of TiO2, is oxidatively dehydrogenated in situ via a Scholl reaction. The reaction, performed at ambient conditions, yields surface adsorbed GMs structurally and electronically equivalent to those synthesized in solution. The new synthetic approach reduces the challenges associated with the tendency of GMs to aggregate and provides a convenient path for integration of GMs into optoelectronic applications. The surface synthesized GMs can be effectively reduced or oxidized via an interfacial charge transfer and can also function as sensitizers for metal oxides in light harvesting applications. Sensitized solar cells (SSCs) prepared from mesoscopic TiO2/GM films and an iodide-based liquid electrolyte show photocurrents of ∼2.5 mA/cm2, an open circuit voltage of ∼0.55 V and fill factor of ∼0.65 under AM 1.5 illumination. The observed power conversion efficiency of η=0.87% is the highest reported efficiency for the GM sensitized solar cell. The performance of the devices was reproducible and stable for a period of at least 3 weeks. We also report first external and internal quantum efficiency measurements for GM SSCs, which point to possible paths for further performance improvements.
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Affiliation(s)
- Zhiqiang Ji
- Chemistry Division, ‡Bioscience Division, §Theory Division, Center for Nonlinear Studies, ∥Materials Physics and Applications Division, Center for Integrated Nanotechnologies, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
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45
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Adamska L, Nayyar I, Chen H, Swan AK, Oldani N, Fernandez-Alberti S, Golder MR, Jasti R, Doorn SK, Tretiak S. Self-trapping of excitons, violation of Condon approximation, and efficient fluorescence in conjugated cycloparaphenylenes. Nano Lett 2014; 14:6539-6546. [PMID: 25310514 DOI: 10.1021/nl503133e] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Cycloparaphenylenes, the simplest structural unit of armchair carbon nanotubes, have unique optoelectronic properties counterintuitive in the class of conjugated organic materials. Our time-dependent density functional theory study and excited state dynamics simulations of cycloparaphenylene chromophores provide a simple and conceptually appealing physical picture explaining experimentally observed trends in optical properties in this family of molecules. Fully delocalized degenerate second and third excitonic states define linear absorption spectra. Self-trapping of the lowest excitonic state due to electron-phonon coupling leads to the formation of spatially localized excitation in large cycloparaphenylenes within 100 fs. This invalidates the commonly used Condon approximation and breaks optical selection rules, making these materials superior fluorophores. This process does not occur in the small molecules, which remain inefficient emitters. A complex interplay of symmetry, π-conjugation, conformational distortion and bending strain controls all photophysics of cycloparaphenylenes.
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Affiliation(s)
- Lyudmyla Adamska
- Theoretical Division, Center for Nonlinear Studies and Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
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46
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Ma X, Roslyak O, Wang F, Duque JG, Piryatinski A, Doorn SK, Htoon H. Influence of exciton dimensionality on spectral diffusion of single-walled carbon nanotubes. ACS Nano 2014; 8:10613-20. [PMID: 25251324 DOI: 10.1021/nn504138m] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
We study temporal evolution of photoluminescence (PL) spectra from individual single-walled carbon nanotubes (SWCNTs) at cryogenic and room temperatures. Sublinear and superlinear correlations between fluctuating PL spectral positions and line widths are observed at cryogenic and room temperatures, respectively. We develop a simple model to explain these two different spectral diffusion behaviors in the framework of quantum-confined Stark effect (QCSE) caused by surface charges trapped in the vicinity of SWCNTs. We show that the wave function properties of excitons, namely, localization at cryogenic temperature and delocalization at room temperature, play a critical role in defining sub- and superlinear correlations. Room temperature PL spectral positions and line widths of SWCNTs coupled to gold dimer nanoantennas on the other hand exhibit sublinear correlations, indicating that excitonic emission mainly originates from nanometer range regions and excitons appear to be localized. Our numerical simulations show that such apparent localization of excitons results from plasmonic confinement of excitation and an enhancement of decay rates in the gap of the dimer nanoantennas.
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Affiliation(s)
- Xuedan Ma
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, ‡Theoretical Division, and §Physical Chemistry and Applied Spectroscopy Group, Chemistry Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
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47
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Ma X, Adamska L, Yamaguchi H, Yalcin SE, Tretiak S, Doorn SK, Htoon H. Electronic structure and chemical nature of oxygen dopant states in carbon nanotubes. ACS Nano 2014; 8:10782-9. [PMID: 25265272 DOI: 10.1021/nn504553y] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We performed low temperature photoluminescence (PL) studies on individual oxygen-doped single-walled carbon nanotubes (SWCNTs) and correlated our observations to electronic structure simulations. Our experiment reveals multiple sharp asymmetric emission peaks at energies 50-300 meV red-shifted from that of the E11 bright exciton peak. Our simulation suggests an association of these peaks with deep trap states tied to different specific chemical adducts. In addition, oxygen doping is also observed to split the E11 exciton into two or more states with an energy splitting <40 meV. We attribute these states to dark states that are brightened through defect-induced symmetry breaking. While the wave functions of these brightened states are delocalized, those of the deep-trap states are strongly localized and pinned to the dopants. These findings are consistent with our experimental observation of asymmetric broadening of the deep trap emission peaks, which can result from interaction between pinned excitons and one-dimensional phonons. Exciton pinning also increases the sensitivity of the deep traps to the local dielectric environment, leading to a large inhomogeneous broadening. Observations of multiple spectral features on single nanotubes indicate the possibility of different chemical adducts coexisting on a given nanotube.
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Affiliation(s)
- Xuedan Ma
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, ‡Theory Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
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48
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Lim YS, Nugraha ART, Cho SJ, Noh MY, Yoon EJ, Liu H, Kim JH, Telg H, Hároz EH, Sanders GD, Baik SH, Kataura H, Doorn SK, Stanton CJ, Saito R, Kono J, Joo T. Ultrafast generation of fundamental and multiple-order phonon excitations in highly enriched (6,5) single-wall carbon nanotubes. Nano Lett 2014; 14:1426-1432. [PMID: 24527806 DOI: 10.1021/nl404536b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Using a macroscopic ensemble of highly enriched (6,5) single-wall carbon nanotubes, combined with high signal-to-noise ratio and time-dependent differential transmission spectroscopy, we have generated vibrational modes in an ultrawide spectral range (10-3000 cm(-1)). A total of 14 modes were clearly resolved and identified, including fundamental modes of A, E1, and E2 symmetries and their combinational modes involving two and three phonons. Through comparison with continuous wave Raman spectra as well as calculations based on an extended tight-binding model, we were able to identify all the observed peaks and determine the frequencies of the individual and combined modes. We provide a full summary of phonon frequencies for (6,5) nanotubes that can serve as a basic reference with which to refine our understanding of nanotube phonon spectra as well as a testbed for new theoretical models.
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Affiliation(s)
- Yong-Sik Lim
- Department of Nano Science and Mechanical Engineering and Nanotechnology Research Center, Konkuk University , Chungju, Chungbuk 380-701, Republic of Korea
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49
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Subbaiyan NK, Cambré S, Parra-Vasquez ANG, Hároz EH, Doorn SK, Duque JG. Role of surfactants and salt in aqueous two-phase separation of carbon nanotubes toward simple chirality isolation. ACS Nano 2014; 8:1619-28. [PMID: 24450507 DOI: 10.1021/nn405934y] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Aqueous two-phase extraction has recently been demonstrated as a new method to separate single-wall carbon nanotubes (SWCNTs). In this work, we determined that the mechanism of separation is driven by the hydrophobicity of the surfactant, or combination of surfactants, at the SWCNT surface. This knowledge allowed us to develop a simple approach for obtaining highly enriched single-chirality suspensions in only 1 or 2 steps. These results were obtained by strategically combining multiple surfactants with different diameter-dependent binding affinities for SWCNTs and salts that readjust the surfactant structure within the mixed micelle surrounding the SWCNTs. The procedure is successfully applied to SWCNTs from different sources (CoMoCAT and HiPco) with various diameter distributions (from 0.53 to 1.2 nm). Each separation step is characterized by optical absorption, resonant Raman, and photoluminescence excitation spectroscopies. By determining the SWCNT sorting mechanism, we were able to develop a new set of parameters that separated another chirality.
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Affiliation(s)
- Navaneetha K Subbaiyan
- Chemistry Division, Physical Chemistry and Applied Spectroscopy Group (C-PCS) and Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory , Los Alamos, New Mexico 87544, United States
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50
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Berciaud S, Li X, Htoon H, Brus LE, Doorn SK, Heinz TF. Intrinsic line shape of the Raman 2D-mode in freestanding graphene monolayers. Nano Lett 2013; 13:3517-3523. [PMID: 23799800 DOI: 10.1021/nl400917e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We report a comprehensive study of the two-phonon intervalley (2D) Raman mode in graphene monolayers, motivated by recent reports of asymmetric 2D-mode line shapes in freestanding graphene. For photon energies in the range 1.53-2.71 eV, the 2D-mode Raman response of freestanding samples appears as bimodal, in stark contrast with the Lorentzian approximation that is commonly used for supported monolayers. The transition between the freestanding and supported cases is mimicked by electrostatically doping freestanding graphene at carrier densities above 2 × 10(11) cm(-2). This result quantitatively demonstrates that low levels of charging can obscure the intrinsically bimodal 2D-mode line shape of monolayer graphene. In pristine freestanding graphene, we observe a broadening of the 2D-mode feature with decreasing photon energy that cannot be rationalized using a simple one-dimensional model based on resonant inner and outer processes. This indicates that phonon wavevectors away from the high-symmetry lines of the Brillouin zone must contribute to the 2D-mode, so that a full two-dimensional calculation is required to properly describe multiphonon-resonant Raman processes.
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Affiliation(s)
- Stéphane Berciaud
- Institut de Physique et Chimie des Matériaux de Strasbourg and NIE, UMR 7504, Université de Strasbourg and CNRS, Strasbourg, France.
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