1
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Sukkabot W. Observation of spin-splitting energies on sp-d exchange interactions tailored in colloidal CdSe/CdMnS core/shell nanoplatelets: an atomistic tight-binding model. Phys Chem Chem Phys 2024; 26:11807-11814. [PMID: 38566596 DOI: 10.1039/d4cp00353e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Using the atomistic tight-binding model plus sp-d exchange term, the embedding of magnetic ions into CdSe/CdMnS core/shell nanoplatelets (NPLs) at different effective temperatures resulted in sp-d exchange interactions, which in turn cause modifications in electronic and magnetic characteristics. The influence of CdMnS monolayers on single-particle spectra, optical band gaps, wave function overlaps and exciton binding energies is more pronounced than that of the effective temperature. Due to the electron, hole and Zeeman splitting energies, with the growth of CdMnS shell monolayers, electron g-factor values are unchanged, but hole and exciton g-factor values are enhanced. Additionally, all g values decrease with increasing temperature, thus representing decreased magnetization of the paramagnetic system. By changing nanoplatelet architectures and temperatures, manipulation of s-d and p-d exchange interactions is accomplished. Overall, studied materials combine the merits of NPLs and magnetic ions, hence leading to alternate possibilities for active applications in spin-based devices.
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Affiliation(s)
- Worasak Sukkabot
- Department of Physics, Faculty of Science, Ubon Ratchathani University, 85 Sathollmark Rd. Warinchamrab, Ubon Ratchathani 34190, Thailand.
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2
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Feng X, Zhai B, Cheng R, Yin L, Wen Y, Jiang J, Wang H, Li Z, Zhu Y, He J. Phase Engineering of 2D Spinel-Type Manganese Oxides. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2304118. [PMID: 37437137 DOI: 10.1002/adma.202304118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 07/10/2023] [Accepted: 07/10/2023] [Indexed: 07/14/2023]
Abstract
2D magnetic materials have been of interest due to their unique long-range magnetic ordering in the low-dimensional regime and potential applications in spintronics. Currently, most studies are focused on strippable van der Waals magnetic materials with layered structures, which typically suffer from a poor stability and scarce species. Spinel oxides have a good environmental stability and rich magnetic properties. However, the isotropic bonding and close-packed nonlayered crystal structure make their 2D growth challenging, let alone the phase engineering. Herein, a phase-controllable synthesis of 2D single-crystalline spinel-type oxides is reported. Using the van der Waals epitaxy strategy, the thicknesses of the obtained tetragonal and hexagonal manganese oxide (Mn3 O4 ) nanosheets can be tuned down to 7.1 nm and one unit cell (0.7 nm), respectively. The magnetic properties of these two phases are evaluated using vibrating-sample magnetometry and first-principle calculations. Both structures exhibit a Curie temperature of 48 K. Owing to its ultrathin geometry, the Mn3 O4 nanosheet exhibits a superior ultraviolet detection performance with an ultralow noise power density of 0.126 pA Hz-1/2 . This study broadens the range of 2D magnetic semiconductors and highlights their potential applications in future information devices.
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Affiliation(s)
- Xiaoqiang Feng
- Key Laboratory of Artificial Micro- and Nanostructures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Baoxing Zhai
- Key Laboratory of Artificial Micro- and Nanostructures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Ruiqing Cheng
- Key Laboratory of Artificial Micro- and Nanostructures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Lei Yin
- Key Laboratory of Artificial Micro- and Nanostructures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Yao Wen
- Key Laboratory of Artificial Micro- and Nanostructures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Jian Jiang
- Key Laboratory of Artificial Micro- and Nanostructures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Hao Wang
- Key Laboratory of Artificial Micro- and Nanostructures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Zhongwei Li
- Key Laboratory of Artificial Micro- and Nanostructures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Yushan Zhu
- Key Laboratory of Artificial Micro- and Nanostructures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Jun He
- Key Laboratory of Artificial Micro- and Nanostructures of Ministry of Education, and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
- Wuhan Institute of Quantum Technology, Wuhan, 430206, China
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3
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Dehnel J, Harchol A, Barak Y, Meir I, Horani F, Shapiro A, Strassberg R, de Mello Donegá C, Demir HV, Gamelin DR, Sharma K, Lifshitz E. Optically detected magnetic resonance spectroscopic analyses on the role of magnetic ions in colloidal nanocrystals. J Chem Phys 2023; 159:071001. [PMID: 37581419 DOI: 10.1063/5.0160787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 07/26/2023] [Indexed: 08/16/2023] Open
Abstract
Incorporating magnetic ions into semiconductor nanocrystals has emerged as a prominent research field for manipulating spin-related properties. The magnetic ions within the host semiconductor experience spin-exchange interactions with photogenerated carriers and are often involved in the recombination routes, stimulating special magneto-optical effects. The current account presents a comparative study, emphasizing the impact of engineering nanostructures and selecting magnetic ions in shaping carrier-magnetic ion interactions. Various host materials, including the II-VI group, halide perovskites, and I-III-VI2 in diverse structural configurations such as core/shell quantum dots, seeded nanorods, and nanoplatelets, incorporated with magnetic ions such as Mn2+, Ni2+, and Cu1+/2+ are highlighted. These materials have recently been investigated by us using state-of-the-art steady-state and transient optically detected magnetic resonance (ODMR) spectroscopy to explore individual spin-dynamics between the photogenerated carriers and magnetic ions and their dependence on morphology, location, crystal composition, and type of the magnetic ion. The information extracted from the analyses of the ODMR spectra in those studies exposes fundamental physical parameters, such as g-factors, exchange coupling constants, and hyperfine interactions, together providing insights into the nature of the carrier (electron, hole, dopant), its local surroundings (isotropic/anisotropic), and spin dynamics. The findings illuminate the importance of ODMR spectroscopy in advancing our understanding of the role of magnetic ions in semiconductor nanocrystals and offer valuable knowledge for designing magnetic materials intended for various spin-related technologies.
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Affiliation(s)
- Joanna Dehnel
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Adi Harchol
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Yahel Barak
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Itay Meir
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Faris Horani
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
| | - Arthur Shapiro
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
- Optical Materials Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, 8092 Zurich, Switzerland
| | - Rotem Strassberg
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Celso de Mello Donegá
- Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science, Utrecht University, 3584 CC Utrecht, The Netherlands
| | - Hilmi Volkan Demir
- Luminous Center of Excellence for Semiconductor Lighting and Displays, TPI, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, School of Materials Science and Engineering, Nanyang Technological University-NTU Singapore, 639798, Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM-Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Türkiye
| | - Daniel R Gamelin
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
| | - Kusha Sharma
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Efrat Lifshitz
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
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4
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Lorenz S, Bieniek J, Erickson CS, Gamelin DR, Fainblat R, Bacher G. Orientation of Individual Anisotropic Nanocrystals Identified by Polarization Fingerprint. ACS NANO 2021; 15:13579-13590. [PMID: 34339182 DOI: 10.1021/acsnano.1c04451] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The polarization of photoluminescence emitted from anisotropic nanocrystals directly reflects the symmetry of the eigenstates involved in the recombination process and can thus be considered as a characteristic feature of a nanocrystal. We performed polarization resolved magneto-photoluminescence spectroscopy on single colloidal Mn2+:CdSe/CdS core-shell quantum dots of wurtzite crystal symmetry. At zero magnetic field, a distinct linear polarization pattern is observed, while applying a magnetic field enforces circularly polarized emission with a characteristic saturation value below 100%. These polarization features are shown to act as a specific fingerprint of each individual nanocrystal. A model considering the orientation of the crystal c⃗ axis with respect to the optical axis and the magnetic field and taking into account the impact of magnetic doping is introduced and quantitatively explains our findings. We demonstrate that a careful analysis of the polarization state of single nanocrystal emission using the full set of Stokes parameters allows for identification of the complete three-dimensional orientation of the crystal anisotropy axis of an individual nanoobject in lab coordinates.
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Affiliation(s)
- Severin Lorenz
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057 Germany
| | - Jan Bieniek
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057 Germany
| | - Christian S Erickson
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Daniel R Gamelin
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Rachel Fainblat
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057 Germany
| | - Gerd Bacher
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057 Germany
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5
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Li C, Hsu SC, Lin JX, Chen JY, Chuang KC, Chang YP, Hsu HS, Chen CH, Lin TS, Liu YH. Giant Zeeman Splitting for Monolayer Nanosheets at Room Temperature. J Am Chem Soc 2020; 142:20616-20623. [PMID: 33249824 DOI: 10.1021/jacs.0c05368] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Giant Zeeman splitting and zero-field splitting (ZFS) are observed in 2D nanosheets that have monolayers of atomic thickness. In this study, single-crystalline CdSe(ethylenediamine)0.5 and Mn2+-doped nanosheets are synthesized via a solvothermal process. Tunable amounts of Mn2+(0.5-8.0%) are introduced, resulting in lattice contraction as well as phosphorescence from five unpaired electrons. The exciton dynamics are dominated by spin-related electronic transitions (4T1 → 6A1) with long lifetimes (20.5, 132, and 295 μs). Temperature-varied EPR spectroscopy with spectral simulation reveals large ZFS (D = 3850 MHz) due to axial distortion of substituted Mn2+ (S = 5/2). In the magnetic circular dichroism (MCD) measurements, we observed giant Zeeman splitting with large effective g values (up to 231 ± 21), which implies huge sp-d exchange interactions in 2D monolayer regimes, leading to diluted magnetic semiconductor (DMS) materials.
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Affiliation(s)
- Chi Li
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan, ROC
| | - Sheng-Chih Hsu
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan, ROC
| | - Jun-Xiao Lin
- Department of Applied Physics, National Pingtung University, Pingtung 90003, Taiwan, ROC
| | - Jou-Yun Chen
- Department of Chemistry, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan, ROC
| | - Kai-Chun Chuang
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan, ROC
| | - Yuan-Pin Chang
- Department of Chemistry, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan, ROC
| | - Hua-Shu Hsu
- Department of Applied Physics, National Pingtung University, Pingtung 90003, Taiwan, ROC
| | - Ching-Hsiang Chen
- Graduate Institute of Applied Science and Technology, National Taiwan University of Science & Technology, Taipei 10673, Taiwan, ROC
| | - Tien-Sung Lin
- Department of Chemistry, Washington University, Saint Louis, Missouri 63130, United States
| | - Yi-Hsin Liu
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan, ROC
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6
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Tolmachev DO, Ivanov VY, Yakovlev DR, Shornikova EV, Witkowski B, Shendre S, Isik F, Delikani S, Demir HV, Bayer M. Optically detected magnetic resonance in CdSe/CdMnS nanoplatelets. NANOSCALE 2020; 12:21932-21939. [PMID: 33112343 DOI: 10.1039/d0nr05633b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Core/shell CdSe/(Cd,Mn)S colloidal nanoplatelets containing magnetic Mn2+ ions are investigated by the optically detected magnetic resonance technique, combining 60 GHz microwave excitation and photoluminescence detection. Resonant heating of the Mn spin system is observed. We identify two mechanisms of optical detection, via variation of either the photoluminescence polarization or its intensity in an external magnetic field. The spin-lattice relaxation dynamics of the Mn spin system is measured and used for evaluation of the Mn concentration. In CdSe/(Cd,Zn,Mn)S nanoplatelets the addition of Zn in the shells significantly broadens the magnetic resonance, evidencing local strain.
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Affiliation(s)
- Danil O Tolmachev
- Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, Germany.
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7
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Dehnel J, Barak Y, Meir I, Budniak AK, Nagvenkar AP, Gamelin DR, Lifshitz E. Insight into the Spin Properties in Undoped and Mn-Doped CdSe/CdS-Seeded Nanorods by Optically Detected Magnetic Resonance. ACS NANO 2020; 14:13478-13490. [PMID: 32935976 DOI: 10.1021/acsnano.0c05454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Controlling the spin degrees of freedom of photogenerated species in semiconductor nanostructures via magnetic doping is an emerging scientific field that may play an important role in the development of new spin-based technologies. The current work explores spin properties in colloidal CdSe/CdS:Mn seeded-nanorod structures doped with a dilute concentration of Mn2+ ions across the rods. The spin properties were determined using continuous-wave optically detected magnetic resonance (ODMR) spectroscopy recorded under variable microwave chopping frequencies. These experiments enabled the deconvolution of a few different radiative recombination processes: band-to-band, trap-to-band, and trap-to-trap emission. The results uncovered the major role of carrier trapping on the spin properties of elongated structures. The magnetic parameters, determined through spin-Hamiltonian simulation of the steady-state ODMR spectra, reflect anisotropy associated with carrier trapping at the seed/rod interface. These observations unveiled changes in the carriers' g-factors and spin-exchange coupling constants as well as extension of radiative and spin-lattice relaxation times due to magnetic coupling between interface carriers and neighboring Mn2+ ions. Overall, this work highlights that the spin degrees of freedom in seeded nanorods are governed by interfacial trapping and can be further manipulated by magnetic doping. These results provide insights into anisotropic nanostructure spin properties relevant to future spin-based technologies.
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Affiliation(s)
- Joanna Dehnel
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Yahel Barak
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Itay Meir
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Adam K Budniak
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Anjani P Nagvenkar
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Daniel R Gamelin
- Department of Chemistry and the Molecular Engineering Materials Center, University of Washington, Box 351700, Seattle, Washington 98195-1700, United States
| | - Efrat Lifshitz
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
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8
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Lorenz S, Erickson CS, Riesner M, Gamelin DR, Fainblat R, Bacher G. Directed Exciton Magnetic Polaron Formation in a Single Colloidal Mn 2+:CdSe/CdS Quantum Dot. NANO LETTERS 2020; 20:1896-1906. [PMID: 31999124 DOI: 10.1021/acs.nanolett.9b05136] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
One of the most prominent signatures of transition-metal doping in colloidal nanocrystals is the formation of charge carrier-induced magnetization of the dopant spin sublattice, called exciton magnetic polaron (EMP). Understanding the direction of EMP formation, however, is still a major obstacle. Here, we present a series of temperature-dependent photoluminescence studies on single colloidal Mn2+:CdSe/CdS core/shell quantum dots (QDs) performed in a vector magnetic field providing a unique insight into the interaction between individual excitons and numerous magnetic impurities. The energy of the QD emission and its full width at half-maximum are controlled by the interplay of EMP formation and statistical magnetic fluctuations, in excellent agreement with theory. Most important, we give the first direct demonstration that anisotropy effects-hypothesized for more than a decade-dominate the direction of EMP formation. Our findings reveal a pathway for directing the orientation of optically induced magnetization in colloidal nanocrystals.
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Affiliation(s)
- Severin Lorenz
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057 Germany
| | - Christian S Erickson
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Maurizio Riesner
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057 Germany
| | - Daniel R Gamelin
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Rachel Fainblat
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057 Germany
| | - Gerd Bacher
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057 Germany
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9
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Fainblat R, Delikanli S, Spee L, Czerny T, Isik F, Sharma VK, Demir HV, Bacher G. Impurity incorporation and exchange interactions in Co2+-doped CdSe/CdS core/shell nanoplatelets. J Chem Phys 2019; 151:224708. [DOI: 10.1063/1.5129391] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Rachel Fainblat
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057, Germany
| | - Savas Delikanli
- Luminous! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, School of Materials Sciences and Engineering, Nanyang Technological University, 639798, Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM-Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Turkey
| | - Leon Spee
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057, Germany
| | - Tamara Czerny
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057, Germany
| | - Furkan Isik
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM-Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Turkey
| | - Vijay Kumar Sharma
- Luminous! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, School of Materials Sciences and Engineering, Nanyang Technological University, 639798, Singapore
| | - Hilmi Volkan Demir
- Luminous! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, School of Materials Sciences and Engineering, Nanyang Technological University, 639798, Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM-Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Turkey
| | - Gerd Bacher
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057, Germany
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10
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Strassberg R, Delikanli S, Barak Y, Dehnel J, Kostadinov A, Maikov G, Hernandez-Martinez PL, Sharma M, Demir HV, Lifshitz E. Persuasive Evidence for Electron-Nuclear Coupling in Diluted Magnetic Colloidal Nanoplatelets Using Optically Detected Magnetic Resonance Spectroscopy. J Phys Chem Lett 2019; 10:4437-4447. [PMID: 31314537 DOI: 10.1021/acs.jpclett.9b01999] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The incorporation of magnetic impurities into semiconductor nanocrystals with size confinement promotes enhanced spin exchange interaction between photogenerated carriers and the guest spins. This interaction stimulates new magneto-optical properties with significant advantages for emerging spin-based technologies. Here we observe and elaborate on carrier-guest interactions in magnetically doped colloidal nanoplatelets with the chemical formula CdSe/Cd1-xMnxS, explored by optically detected magnetic resonance and magneto-photoluminescence spectroscopy. The host matrix, with a quasi-type II electronic configuration, introduces a dominant interaction between a photogenerated electron and a magnetic dopant. Furthermore, the data convincingly presents the interaction between an electron and nuclear spins of the doped ions located at neighboring surroundings, with consequent influence on the carrier's spin relaxation time. The nuclear spin contribution by the magnetic dopants in colloidal nanoplatelets is considered here for the first time.
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Affiliation(s)
- Rotem Strassberg
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute , Technion-Israel Institute of Technology , Haifa 32000 , Israel
| | - Savas Delikanli
- Luminous Center of Excellence for Semiconductor Lighting and Displays, TPI, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, School of Materials Science and Engineering , Nanyang Technological University-NTU Singapore , 639798 Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM-Institute of Materials Science and Nanotechnology , Bilkent University , Ankara 06800 , Turkey
| | - Yahel Barak
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute , Technion-Israel Institute of Technology , Haifa 32000 , Israel
| | - Joanna Dehnel
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute , Technion-Israel Institute of Technology , Haifa 32000 , Israel
| | - Alyssa Kostadinov
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute , Technion-Israel Institute of Technology , Haifa 32000 , Israel
| | - Georgy Maikov
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute , Technion-Israel Institute of Technology , Haifa 32000 , Israel
| | - Pedro Ludwig Hernandez-Martinez
- Luminous Center of Excellence for Semiconductor Lighting and Displays, TPI, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, School of Materials Science and Engineering , Nanyang Technological University-NTU Singapore , 639798 Singapore
| | - Manoj Sharma
- Luminous Center of Excellence for Semiconductor Lighting and Displays, TPI, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, School of Materials Science and Engineering , Nanyang Technological University-NTU Singapore , 639798 Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM-Institute of Materials Science and Nanotechnology , Bilkent University , Ankara 06800 , Turkey
| | - Hilmi Volkan Demir
- Luminous Center of Excellence for Semiconductor Lighting and Displays, TPI, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, School of Materials Science and Engineering , Nanyang Technological University-NTU Singapore , 639798 Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM-Institute of Materials Science and Nanotechnology , Bilkent University , Ankara 06800 , Turkey
| | - Efrat Lifshitz
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute , Technion-Israel Institute of Technology , Haifa 32000 , Israel
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11
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Muckel F, Delikanli S, Hernández-Martínez PL, Priesner T, Lorenz S, Ackermann J, Sharma M, Demir HV, Bacher G. sp-d Exchange Interactions in Wave Function Engineered Colloidal CdSe/Mn:CdS Hetero-Nanoplatelets. NANO LETTERS 2018; 18:2047-2053. [PMID: 29464958 DOI: 10.1021/acs.nanolett.8b00060] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In two-dimensional (2D) colloidal semiconductor nanoplatelets, which are atomically flat nanocrystals, the precise control of thickness and composition on the atomic scale allows for the synthesis of heterostructures with well-defined electron and hole wave function distributions. Introducing transition metal dopants with a monolayer precision enables tailored magnetic exchange interactions between dopants and band states. Here, we use the absorption based technique of magnetic circular dichroism (MCD) to directly prove the exchange coupling of magnetic dopants with the band charge carriers in hetero-nanoplatelets with CdSe core and manganese-doped CdS shell (CdSe/Mn:CdS). We show that the strength of both the electron as well as the hole exchange interactions with the dopants can be tuned by varying the nanoplatelets architecture with monolayer accuracy. As MCD is highly sensitive for excitonic resonances, excited level spectroscopy allows us to resolve and identify, in combination with wave function calculations, several excited state transitions including spin-orbit split-off excitonic contributions. Thus, our study not only demonstrates the possibility to expand the extraordinary physical properties of colloidal nanoplatelets toward magneto-optical functionality by transition metal doping but also provides an insight into the excited state electronic structure in this novel two-dimensional material.
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Affiliation(s)
- Franziska Muckel
- Werkstoffe der Elektrotechnik and CENIDE , University Duisburg-Essen , Bismarckstraße 81 , 47057 Duisburg , Germany
| | - Savas Delikanli
- LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, School of Materials Sciences and Engineering , Nanyang Technological University 639798 , Singapore
| | - Pedro Ludwig Hernández-Martínez
- LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, School of Materials Sciences and Engineering , Nanyang Technological University 639798 , Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology , Bilkent University , Ankara 06800 , Turkey
| | - Tamara Priesner
- Werkstoffe der Elektrotechnik and CENIDE , University Duisburg-Essen , Bismarckstraße 81 , 47057 Duisburg , Germany
| | - Severin Lorenz
- Werkstoffe der Elektrotechnik and CENIDE , University Duisburg-Essen , Bismarckstraße 81 , 47057 Duisburg , Germany
| | - Julia Ackermann
- Werkstoffe der Elektrotechnik and CENIDE , University Duisburg-Essen , Bismarckstraße 81 , 47057 Duisburg , Germany
| | - Manoj Sharma
- LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, School of Materials Sciences and Engineering , Nanyang Technological University 639798 , Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology , Bilkent University , Ankara 06800 , Turkey
| | - Hilmi Volkan Demir
- LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, School of Materials Sciences and Engineering , Nanyang Technological University 639798 , Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology , Bilkent University , Ankara 06800 , Turkey
| | - Gerd Bacher
- Werkstoffe der Elektrotechnik and CENIDE , University Duisburg-Essen , Bismarckstraße 81 , 47057 Duisburg , Germany
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12
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Kormilina TK, Cherevkov SA, Fedorov AV, Baranov AV. Cadmium Chalcogenide Nano-Heteroplatelets: Creating Advanced Nanostructured Materials by Shell Growth, Substitution, and Attachment. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2017; 13:1702300. [PMID: 28895307 DOI: 10.1002/smll.201702300] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 07/24/2017] [Indexed: 06/07/2023]
Abstract
The current direction in the evolution of 2D semiconductor nanocrystals involves the combination of metal and semiconductor components to form new nanoengineered materials called nano-heteroplatelets. This Review covers different heterostructure architectures that can be applied to cadmium chalcogenide nanoplatelets, including variously shaped shell, metal nanoparticle decoration, and doped and alloy systems. Here, for the first time a complete classification of nano-heteroplatelet types is provided with recommended notations and a systematization of the existing knowledge and experience concerning heterostructure formation techniques, addressing the morphology, optoelectronic and magnetic properties, and novel features of different heterostructures. This Review is also devoted to possible applications of these heterostructures and of one-component nanoplatelets in multiple fields, including light-emitting devices and biological imaging.
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Affiliation(s)
- Tatiana K Kormilina
- Department of Optical Physics and Modern Natural Science, ITMO University, 49 Kronverksky Pr, St. Petersburg, 197101, Russia
| | - Sergei A Cherevkov
- Department of Optical Physics and Modern Natural Science, ITMO University, 49 Kronverksky Pr, St. Petersburg, 197101, Russia
| | - Anatoly V Fedorov
- Department of Optical Physics and Modern Natural Science, ITMO University, 49 Kronverksky Pr, St. Petersburg, 197101, Russia
| | - Alexander V Baranov
- Department of Optical Physics and Modern Natural Science, ITMO University, 49 Kronverksky Pr, St. Petersburg, 197101, Russia
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13
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Kubie L, King LA, Kern ME, Murphy JR, Kattel S, Yang Q, Stecher JT, Rice WD, Parkinson BA. Synthesis and Characterization of Ultrathin Silver Sulfide Nanoplatelets. ACS NANO 2017; 11:8471-8477. [PMID: 28752997 DOI: 10.1021/acsnano.7b04280] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We report the synthesis of ultrathin silver sulfide (Ag2S) nanoplatelets (NPLs) synthesized via a one-pot method in ethylene glycol with 3-mercaptopropionic acid serving as both the sulfur precursor and the platelet ligand. The colloidally synthesized nanoplatelets are exceptionally thin, with a thickness of only 3.5 ± 0.2 Å and a 1S exciton Bohr diameter to confinement ratio of ∼12.6. The NPL growth is shown to be quantized by layer thickness using absorption and photoluminescence (PL) spectroscopy. Transmission electron microscopy, atomic force microscopy, and X-ray diffraction analyses of the NPLs show that they correspond to the (202) plane of the β-Ag2S structure. The PL quantum yield of these NPLs is ∼30%, suggesting their potential use in biomedical imaging. Optoelectronic properties were evaluated via sensitized photocurrent spectroscopy with the resulting spectra closely matching the distinctive absorption spectral shape of the Ag2S NPLs.
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Affiliation(s)
- Lenore Kubie
- Department of Chemistry and ‡Department of Physics, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Laurie A King
- Department of Chemistry and ‡Department of Physics, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Meghan E Kern
- Department of Chemistry and ‡Department of Physics, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Joseph R Murphy
- Department of Chemistry and ‡Department of Physics, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Subash Kattel
- Department of Chemistry and ‡Department of Physics, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Qian Yang
- Department of Chemistry and ‡Department of Physics, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Joshua T Stecher
- Department of Chemistry and ‡Department of Physics, University of Wyoming , Laramie, Wyoming 82071, United States
| | - William D Rice
- Department of Chemistry and ‡Department of Physics, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Bruce A Parkinson
- Department of Chemistry and ‡Department of Physics, University of Wyoming , Laramie, Wyoming 82071, United States
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14
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Rice WD, Liu W, Pinchetti V, Yakovlev DR, Klimov VI, Crooker SA. Direct Measurements of Magnetic Polarons in Cd 1-xMn xSe Nanocrystals from Resonant Photoluminescence. NANO LETTERS 2017; 17:3068-3075. [PMID: 28388078 DOI: 10.1021/acs.nanolett.7b00421] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In semiconductors, quantum confinement can greatly enhance the interaction between band carriers (electrons and holes) and dopant atoms. One manifestation of this enhancement is the increased stability of exciton magnetic polarons in magnetically doped nanostructures. In the limit of very strong 0D confinement that is realized in colloidal semiconductor nanocrystals, a single exciton can exert an effective exchange field Bex on the embedded magnetic dopants that exceeds several tesla. Here we use the very sensitive method of resonant photoluminescence (PL) to directly measure the presence and properties of exciton magnetic polarons in colloidal Cd1-xMnxSe nanocrystals. Despite small Mn2+ concentrations (x = 0.4-1.6%), large polaron binding energies up to ∼26 meV are observed at low temperatures via the substantial Stokes shift between the pump laser and the resonant PL maximum, indicating nearly complete alignment of all Mn2+ spins by Bex. Temperature and magnetic field-dependent studies reveal that Bex ≈ 10 T in these nanocrystals, in good agreement with theoretical estimates. Further, the emission line widths provide direct insight into the statistical fluctuations of the Mn2+ spins. These resonant PL studies provide detailed insight into collective magnetic phenomena, especially in lightly doped nanocrystals where conventional techniques such as nonresonant PL or time-resolved PL provide ambiguous results.
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Affiliation(s)
- W D Rice
- Department of Physics and Astronomy, University of Wyoming , Laramie, Wyoming 82071, United States
| | | | - V Pinchetti
- Dipartimento di Scienza dei Materiali, Università degli Studi di Milano-Bicocca , Via Cozzi 55, IT-20125 Milano, Italy
| | - D R Yakovlev
- Experimentelle Physik 2, Technische Universität Dortmund , D-44221 Dortmund, Germany
- Ioffe Institute, Russian Academy of Sciences , 194021 St. Petersburg, Russia
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15
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Pandey A, Sarma DD. Recent Advances in Manganese Doped II-VI Semiconductor Quantum Dots. Z Anorg Allg Chem 2016. [DOI: 10.1002/zaac.201600368] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Anshu Pandey
- Solid State and Structural Chemistry Unit; Indian Institute of Science; 560012 Bangalore India
| | - Dipankar Das Sarma
- Solid State and Structural Chemistry Unit; Indian Institute of Science; 560012 Bangalore India
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16
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Fainblat R, Barrows CJ, Hopmann E, Siebeneicher S, Vlaskin VA, Gamelin DR, Bacher G. Giant Excitonic Exchange Splittings at Zero Field in Single Colloidal CdSe Quantum Dots Doped with Individual Mn 2+ Impurities. NANO LETTERS 2016; 16:6371-6377. [PMID: 27646931 DOI: 10.1021/acs.nanolett.6b02775] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Replacing a single atom of a host semiconductor nanocrystal with a functional dopant can introduce completely new properties potentially valuable for "solotronic" information-processing applications. Here, we report successful doping of colloidal CdSe quantum dots with a very small number of manganese ions-down to the ultimate limit of one. Single-particle spectroscopy reveals spectral fingerprints of the spin-spin interactions between individual dopants and quantum-dot excitons. Spectrally well-resolved emission peaks are observed that can be related to the discrete spin projections of individual Mn2+ ions. In agreement with theoretical predictions, the exchange splittings are enhanced by more than an order of magnitude in these quantum dots compared to their epitaxial counterparts, opening a path for solotronic applications at elevated temperatures.
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Affiliation(s)
- Rachel Fainblat
- Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstr. 81, Duisburg, 47057 Germany
- Department of Chemistry, University of Washington , Seattle, Washington 98195-1700, United States
| | - Charles J Barrows
- Department of Chemistry, University of Washington , Seattle, Washington 98195-1700, United States
| | - Eric Hopmann
- Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstr. 81, Duisburg, 47057 Germany
| | - Simon Siebeneicher
- Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstr. 81, Duisburg, 47057 Germany
| | - Vladmir A Vlaskin
- Department of Chemistry, University of Washington , Seattle, Washington 98195-1700, United States
| | - Daniel R Gamelin
- Department of Chemistry, University of Washington , Seattle, Washington 98195-1700, United States
| | - Gerd Bacher
- Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstr. 81, Duisburg, 47057 Germany
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17
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Muckel F, Yang J, Lorenz S, Baek W, Chang H, Hyeon T, Bacher G, Fainblat R. Digital Doping in Magic-Sized CdSe Clusters. ACS NANO 2016; 10:7135-41. [PMID: 27420556 DOI: 10.1021/acsnano.6b03348] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Magic-sized semiconductor clusters represent an exciting class of materials located at the boundary between quantum dots and molecules. It is expected that replacing single atoms of the host crystal with individual dopants in a one-by-one fashion can lead to unique modifications of the material properties. Here, we demonstrate the dependence of the magneto-optical response of (CdSe)13 clusters on the discrete number of Mn(2+) ion dopants. Using time-of-flight mass spectrometry, we are able to distinguish undoped, monodoped, and bidoped cluster species, allowing for an extraction of the relative amount of each species for a specific average doping concentration. A giant magneto-optical response is observed up to room temperature with clear evidence that exclusively monodoped clusters are magneto-optically active, whereas the Mn(2+) ions in bidoped clusters couple antiferromagnetically and are magneto-optically passive. Mn(2+)-doped clusters therefore represent a system where magneto-optical functionality is caused by solitary dopants, which might be beneficial for future solotronic applications.
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Affiliation(s)
- Franziska Muckel
- Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstraße 81, 47057 Duisburg, Germany
| | - Jiwoong Yang
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea
| | - Severin Lorenz
- Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstraße 81, 47057 Duisburg, Germany
| | - Woonhyuk Baek
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea
| | - Hogeun Chang
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea
| | - Taeghwan Hyeon
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea
| | - Gerd Bacher
- Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstraße 81, 47057 Duisburg, Germany
| | - Rachel Fainblat
- Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstraße 81, 47057 Duisburg, Germany
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea
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18
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Rice WD, Liu W, Baker TA, Sinitsyn NA, Klimov VI, Crooker SA. Revealing giant internal magnetic fields due to spin fluctuations in magnetically doped colloidal nanocrystals. NATURE NANOTECHNOLOGY 2016; 11:137-142. [PMID: 26595331 DOI: 10.1038/nnano.2015.258] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 10/06/2015] [Indexed: 06/05/2023]
Abstract
Strong quantum confinement in semiconductors can compress the wavefunctions of band electrons and holes to nanometre-scale volumes, significantly enhancing interactions between themselves and individual dopants. In magnetically doped semiconductors, where paramagnetic dopants (such as Mn(2+), Co(2+) and so on) couple to band carriers via strong sp-d spin exchange, giant magneto-optical effects can therefore be realized in confined geometries using few or even single impurity spins. Importantly, however, thermodynamic spin fluctuations become increasingly relevant in this few-spin limit. In nanoscale volumes, the statistical fluctuations of N spins are expected to generate giant effective magnetic fields Beff, which should dramatically impact carrier spin dynamics, even in the absence of any applied field. Here we directly and unambiguously reveal the large Beff that exist in Mn(2+)-doped CdSe colloidal nanocrystals using ultrafast optical spectroscopy. At zero applied magnetic field, extremely rapid (300-600 GHz) spin precession of photoinjected electrons is observed, indicating Beff ∼ 15 -30 T for electrons. Precession frequencies exceed 2 THz in applied magnetic fields. These signals arise from electron precession about the random fields due to statistically incomplete cancellation of the embedded Mn(2+) moments, thereby revealing the initial coherent dynamics of magnetic polaron formation, and highlighting the importance of magnetization fluctuations on carrier spin dynamics in nanomaterials.
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Affiliation(s)
- William D Rice
- National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Wenyong Liu
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Thomas A Baker
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Nikolai A Sinitsyn
- Theory Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Victor I Klimov
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Scott A Crooker
- National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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19
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Delikanli S, Akgul MZ, Murphy JR, Barman B, Tsai Y, Scrace T, Zhang P, Bozok B, Hernández-Martínez PL, Christodoulides J, Cartwright AN, Petrou A, Demir HV. Mn(2+)-Doped CdSe/CdS Core/Multishell Colloidal Quantum Wells Enabling Tunable Carrier-Dopant Exchange Interactions. ACS NANO 2015; 9:12473-12479. [PMID: 26567872 DOI: 10.1021/acsnano.5b05903] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In this work, we report the manifestations of carrier-dopant exchange interactions in colloidal Mn(2+)-doped CdSe/CdS core/multishell quantum wells. The carrier-magnetic ion exchange interaction effects are tunable through wave function engineering. In our quantum well heterostructures, manganese was incorporated by growing a Cd0.985Mn0.015S monolayer shell on undoped CdSe nanoplatelets using the colloidal atomic layer deposition technique. Unlike previously synthesized Mn(2+)-doped colloidal nanostructures, the location of the Mn ions was controlled with atomic layer precision in our heterostructures. This is realized by controlling the spatial overlap between the carrier wave functions with the manganese ions by adjusting the location, composition, and number of the CdSe, Cd1-xMnxS, and CdS layers. The photoluminescence quantum yield of our magnetic heterostructures was found to be as high as 20% at room temperature with a narrow photoluminescence bandwidth of ∼22 nm. Our colloidal quantum wells, which exhibit magneto-optical properties analogous to those of epitaxially grown quantum wells, offer new opportunities for solution-processed spin-based semiconductor devices.
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Affiliation(s)
- Savas Delikanli
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey
| | - Mehmet Zafer Akgul
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey
| | - Joseph R Murphy
- Department of Physics, SUNY at Buffalo , Amherst, New York 14260, United States
| | - Biplob Barman
- Department of Physics, SUNY at Buffalo , Amherst, New York 14260, United States
| | - Yutsung Tsai
- Department of Physics, SUNY at Buffalo , Amherst, New York 14260, United States
| | - Thomas Scrace
- Department of Physics, SUNY at Buffalo , Amherst, New York 14260, United States
| | - Peiyao Zhang
- Department of Physics, SUNY at Buffalo , Amherst, New York 14260, United States
| | - Berkay Bozok
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey
| | - Pedro Ludwig Hernández-Martínez
- LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, Nanyang Technological University , Singapore 639798
| | | | | | - Athos Petrou
- Department of Physics, SUNY at Buffalo , Amherst, New York 14260, United States
| | - Hilmi Volkan Demir
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey
- LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, Nanyang Technological University , Singapore 639798
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20
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Yang J, Fainblat R, Kwon SG, Muckel F, Yu JH, Terlinden H, Kim BH, Iavarone D, Choi MK, Kim IY, Park I, Hong HK, Lee J, Son JS, Lee Z, Kang K, Hwang SJ, Bacher G, Hyeon T. Route to the Smallest Doped Semiconductor: Mn2+-Doped (CdSe)13 Clusters. J Am Chem Soc 2015; 137:12776-9. [DOI: 10.1021/jacs.5b07888] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jiwoong Yang
- Center
for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 151-742, Republic of Korea
| | - Rachel Fainblat
- Werkstoffe
der Elektrotechnik und CENIDE, Universität Duisburg-Essen, 47057 Duisburg, Germany
| | - Soon Gu Kwon
- Center
for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 151-742, Republic of Korea
| | - Franziska Muckel
- Werkstoffe
der Elektrotechnik und CENIDE, Universität Duisburg-Essen, 47057 Duisburg, Germany
| | - Jung Ho Yu
- Center
for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 151-742, Republic of Korea
| | - Hendrik Terlinden
- Werkstoffe
der Elektrotechnik und CENIDE, Universität Duisburg-Essen, 47057 Duisburg, Germany
| | - Byung Hyo Kim
- Center
for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 151-742, Republic of Korea
| | - Dino Iavarone
- Werkstoffe
der Elektrotechnik und CENIDE, Universität Duisburg-Essen, 47057 Duisburg, Germany
| | - Moon Kee Choi
- Center
for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 151-742, Republic of Korea
| | - In Young Kim
- Materials
Research Institute for Clean Energy, Department of Chemistry and Nano
Sciences, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Inchul Park
- Center
for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 151-742, Republic of Korea
| | - Hyo-Ki Hong
- School of
Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 689-798, Republic of Korea
| | - Jihwa Lee
- Center
for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 151-742, Republic of Korea
| | - Jae Sung Son
- School of
Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 689-798, Republic of Korea
| | - Zonghoon Lee
- School of
Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 689-798, Republic of Korea
| | - Kisuk Kang
- Center
for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 151-742, Republic of Korea
| | - Seong-Ju Hwang
- Materials
Research Institute for Clean Energy, Department of Chemistry and Nano
Sciences, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Gerd Bacher
- Werkstoffe
der Elektrotechnik und CENIDE, Universität Duisburg-Essen, 47057 Duisburg, Germany
| | - Taeghwan Hyeon
- Center
for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 151-742, Republic of Korea
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21
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Fainblat R, Muckel F, Barrows CJ, Vlaskin VA, Gamelin DR, Bacher G. Valence-band mixing effects in the upper-excited-state magneto-optical responses of colloidal Mn2+-doped CdSe quantum dots. ACS NANO 2014; 8:12669-12675. [PMID: 25438717 DOI: 10.1021/nn505610e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present an experimental study of the magneto-optical activity of multiple excited excitonic states of manganese-doped CdSe quantum dots chemically prepared by the diffusion doping method. Giant excitonic Zeeman splittings of each of these excited states can be extracted for a series of quantum dot sizes and are found to depend on the radial quantum number of the hole envelope function involved in each transition. As seven out of eight transitions involve the same electron energy state, 1Se, the dominant hole character of each excitonic transition can be identified, making use of the fact that the g-factor of the pure heavy-hole component has a different sign compared to pure light hole or split-off components. Because the magnetic exchange interactions are sensitive to hole state mixing, the giant Zeeman splittings reported here provide clear experimental evidence of quantum-size-induced mixing among valence-band states in nanocrystals.
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Affiliation(s)
- Rachel Fainblat
- Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstraße 81, Duisburg, 47057 Germany
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22
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Yan K, Zhang L, Kuang Q, Wei Z, Yi Y, Wang J, Yang S. Solution-processed, barrier-confined, and 1D nanostructure supported quasi-quantum well with large photoluminescence enhancement. ACS NANO 2014; 8:3771-3780. [PMID: 24580094 DOI: 10.1021/nn500465w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Planar substrate supported semiconductor quantum well (QW) structures are not amenable to manipulation in miniature devices, while free-standing QW nanostructures, e.g., ultrathin nanosheets and nanoribbons, suffer from mechanical and environmental instability. Therefore, it is tempting to fashion high-quality QW structures on anisotropic and mechanically robust supporting nanostructures such as nanowires and nanoplates. Herein, we report a solution quasi-heteroepitaxial route for growing a barrier-confined quasi-QW structure (ZnSe/CdSe/ZnSe) on the supporting arms of ZnO nanotetrapods, which have a 1D nanowire structure, through the combination of ion exchange and successive deposition assembly. This resulted in highly crystalline and highly oriented quasi-QWs along the whole axial direction of the arms of the nanotetrapod because a transition buffer layer (Zn(x)Cd(1-x)Se) was formed and in turn reduced the lattice mismatch and surface defects. Significantly, such a barrier-confined QW emits excitonic light ∼17 times stronger than the heterojunction (HJ)-type structure (ZnSe/CdSe, HJ) at the single-particle level. Time-resolved photoluminescence from ensemble QWs exhibits a lifetime of 10 ns, contrasting sharply with ∼300 ps for the control HJ sample. Single-particle PL and Raman spectra suggest that the barrier layer of QW has completely removed the surface trap states on the HJ and restored or upgraded the photoelectric properties of the semiconductor layer. Therefore, this deliberate heteroepitaxial growth protocol on the supporting nanotetrapod has realized a several micrometer long QW structure with high mechanical robustness and high photoelectric quality. We envision that such QWs integrated on 1D nanostructures will largely improve the performance of solar cells and bioprobes, among others.
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Affiliation(s)
- Keyou Yan
- Nano Science and Technology Program, Department of Chemistry, and ‡Department of Physics, William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong
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