1
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Ye Y, Lin X, Fang W. Room-Temperature Single-Photon Sources Based on Colloidal Quantum Dots: A Review. MATERIALS (BASEL, SWITZERLAND) 2023; 16:7684. [PMID: 38138825 PMCID: PMC10744688 DOI: 10.3390/ma16247684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 12/06/2023] [Accepted: 12/13/2023] [Indexed: 12/24/2023]
Abstract
Single-photon sources (SPSs) play a crucial role in quantum photonics, and colloidal quantum dots (CQDs) have emerged as promising and cost-effective candidates for such applications due to their high-purity single-photon emission at room temperature. This review focuses on various aspects of CQDs as SPSs. Firstly, a brief overview of the fundamental optical properties of CQDs is provided, including emission wavelength engineering and fluorescence intermittency, and their single-photon emission properties. Subsequently, this review delves into research concerning CQDs as SPSs, covering topics such as the coupling of single CQDs to microcavities, both in weak and strong coupling regimes. Additionally, methods for localizing and positioning CQDs are explored, which are critical for on-chip SPSs devices.
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Affiliation(s)
- Yongzheng Ye
- Interdisciplinary Center for Quantum Information, State Key Laboratory of Extreme Photonics and Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China;
| | - Xing Lin
- College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China;
| | - Wei Fang
- Interdisciplinary Center for Quantum Information, State Key Laboratory of Extreme Photonics and Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China;
- Key Laboratory of Excited-State Materials of Zhejiang Province, Zhejiang University, Hangzhou 310027, China
- Jiaxing Key Laboratory of Photonic Sensing & Intelligent Imaging, Jiaxing 314000, China
- Intelligent Optics & Photonics Research Center, Jiaxing Research Institute Zhejiang University, Jiaxing 314000, China
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2
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Praturi A, Schrod S, Singh BP, Vasa P. White-Light Spectral Interferometry for Characterizing Inhomogeneity in Solutions and Nanocolloids. ACS NANOSCIENCE AU 2022; 2:486-493. [PMID: 37101849 PMCID: PMC10125346 DOI: 10.1021/acsnanoscienceau.2c00014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 07/05/2022] [Accepted: 07/06/2022] [Indexed: 11/28/2022]
Abstract
We demonstrate the use of white-light spectral interferometry as an effective technique involving only linear optical interactions and a partially coherent light source to measure the complex transmission response function of optical resonance and to determine the corresponding variation in the refractive index relative to a reference. We also discuss experimental arrangements to increase the accuracy and sensitivity of the technique. The superiority of the technique over single-beam absorption measurements is demonstrated by the accurate determination of the response function of the chlorophyll-a solution. The technique is then applied to chlorophyll-a solutions of varying concentrations and gold nanocolloids to characterize inhomogeneous broadening. Results on the inhomogeneity of gold nanocolloids are also supported by transmission electron micrographs, showing distributions of the size and shape of the constituent gold nanorods.
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Affiliation(s)
- Aparna Praturi
- Department of Physics, Indian Institute of Technology Bombay, 400076 Mumbai, India
| | - Stefan Schrod
- Department of Physics, University of Regensburg, 93053 Regensburg, Germany
| | - Bhanu Pratap Singh
- Department of Physics, Indian Institute of Technology Bombay, 400076 Mumbai, India
| | - Parinda Vasa
- Department of Physics, Indian Institute of Technology Bombay, 400076 Mumbai, India
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3
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Zirkelbach J, Mirzaei M, Deperasinska I, Kozankiewicz B, Gurlek B, Shkarin A, Utikal T, Götzinger S, Sandoghdar V. High-resolution vibronic spectroscopy of a single molecule embedded in a crystal. J Chem Phys 2022; 156:104301. [DOI: 10.1063/5.0081297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | | | | | - Boleslaw Kozankiewicz
- Radiation Physics and Spectroscopy, Institute of Physics Polish Academy of Sciences, Poland
| | - Burak Gurlek
- Sandoghdar Division, Max Planck Institute for the Science of Light, Germany
| | | | - Tobias Utikal
- Max Planck Institute for the Science of Light, Germany
| | | | - Vahid Sandoghdar
- Division Sandoghdar, Max Planck Institute for the Science of Light, Germany
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4
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Feng S, Qin Q, Han X, Zhang C, Wang X, Yu T, Xiao M. Universal Existence of Localized Single-Photon Emitters in the Perovskite Film of All-Inorganic CsPbBr 3 Microcrystals. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2106278. [PMID: 34687093 DOI: 10.1002/adma.202106278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/17/2021] [Indexed: 06/13/2023]
Abstract
All-inorganic halide perovskites have drawn a lot of research attention very recently owing to their potential solution to the instability issue currently faced by the organic-inorganic counterparts. Meanwhile, the halide perovskites in a solid film are manifested as microscale morphologies whose functionalities are unavoidably affected by the interior or exterior presence of various nanoscale entities. Here all-inorganic solid films are fabricated with varying densities of single CsPbBr3 microcrystals, showing that very sharp photoluminescence peaks can be universally observed at 4 K with the linewidths being as narrow as hundreds of μeV. The single-photon emission nature is confirmed for such a photoluminescence peak, whose intensity is completely quenched above ≈30 K to suggest its possible origin from a low potential-energy region of the single microcrystal. The discovery of such a novel emitting species in halide perovskites, with the enriched structure-property relationship, will surely impart significant influences on the advancement of relevant optoelectronic devices and quantum-light sources.
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Affiliation(s)
- Shengnan Feng
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Qilin Qin
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Xiaopeng Han
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Chunfeng Zhang
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Xiaoyong Wang
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Tao Yu
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Min Xiao
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- Department of Physics, University of Arkansas, Fayetteville, AR, 72701, USA
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5
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Zhao H, Pettes MT, Zheng Y, Htoon H. Site-controlled telecom-wavelength single-photon emitters in atomically-thin MoTe 2. Nat Commun 2021; 12:6753. [PMID: 34799576 PMCID: PMC8604946 DOI: 10.1038/s41467-021-27033-w] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 10/29/2021] [Indexed: 11/09/2022] Open
Abstract
Quantum emitters (QEs) in two-dimensional transition metal dichalcogenides (2D TMDCs) have advanced to the forefront of quantum communication and transduction research. To date, QEs capable of operating in O-C telecommunication bands have not been demonstrated in TMDCs. Here we report site-controlled creation of telecom QEs emitting over the 1080 to 1550 nm telecommunication wavelength range via coupling of 2D molybdenum ditelluride (MoTe2) to strain inducing nano-pillar arrays. Hanbury Brown and Twiss experiments conducted at 10 K reveal clear photon antibunching with 90% single-photon purity. The photon antibunching can be observed up to liquid nitrogen temperature (77 K). Polarization analysis further reveals that while some QEs display cross-linearly polarized doublets with ~1 meV splitting resulting from the strain induced anisotropic exchange interaction, valley degeneracy is preserved in other QEs. Valley Zeeman splitting as well as restoring of valley symmetry in cross-polarized doublets are observed under 8 T magnetic field. Single-photon emitters in 2D semiconductors hold promise for quantum applications, but usually operate in the 500-800 nm wavelength range. Here, the authors report site-controlled creation of quantum emitters in the telecommunication wavelength window by coupling 2D MoTe2 to strain inducing nano-pillar arrays.
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Affiliation(s)
- Huan Zhao
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA.
| | - Michael T Pettes
- Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA
| | - Yu Zheng
- 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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6
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Safwan SA, El Meshad N. Stability of Excited Exciton States in Semiconductor Quantum Dots Under a Lateral Electric Field. INTERNATIONAL JOURNAL OF NANOSCIENCE 2021. [DOI: 10.1142/s0219581x21500393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The effect of the lateral electric field (LEF) on the excited and ground state stability of an exciton ([Formula: see text]) confined in a parabolic cylindrical quantum dot (QD) was estimated in this study. The calculation was performed in the framework of single-band effective mass theory using a variational approach. Our results revealed that the ground state binding energy of [Formula: see text] decreases with increasing the cylindrical QD radius until the exciton stability is lost at moderate LEF strength. By increasing the LEF strength, the excited heavy-hole ([Formula: see text]) can create an excited state [Formula: see text] or excited state [Formula: see text] of [Formula: see text], and the results indicate that the first state is more stable. In contrast, when an excited electron ([Formula: see text]) combines with an excited hole ([Formula: see text]) or unexcited hole ([Formula: see text]), it contains no split excited states for [Formula: see text] with less binding energy than the state [Formula: see text]. Comparing our previous results of donor impurity [Formula: see text] with [Formula: see text], we found that [Formula: see text] has a more stable ground state than [Formula: see text]. Moreover, the excited [Formula: see text] states are more stable than the excited states of [Formula: see text]. The quantum Stark shift (QSS) of the light- and heavy-hole exciton energy was explored, and a blue-shifted and quadratic QSS was observed. In contrast, for single particles (electron, heavy-hole and light hole), a red-shifted and linear QSS was observed.
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Affiliation(s)
- S. A. Safwan
- Theoretical Physics Department, National Research Centre, Dokki, Cairo, Egypt
| | - Nagwa El Meshad
- Theoretical Physics Department, National Research Centre, Dokki, Cairo, Egypt
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7
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Boras G, Yu X, Fonseka HA, Davis G, Velichko AV, Gott JA, Zeng H, Wu S, Parkinson P, Xu X, Mowbray D, Sanchez AM, Liu H. Self-Catalyzed AlGaAs Nanowires and AlGaAs/GaAs Nanowire-Quantum Dots on Si Substrates. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2021; 125:14338-14347. [PMID: 34276869 PMCID: PMC8279736 DOI: 10.1021/acs.jpcc.1c03680] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 06/11/2021] [Indexed: 06/13/2023]
Abstract
Self-catalyzed AlGaAs nanowires (NWs) and NWs with a GaAs quantum dot (QD) were monolithically grown on Si(111) substrates via solid-source molecular beam epitaxy. This growth technique is advantageous in comparison to the previously employed Au-catalyzed approach, as it removes Au contamination issues and renders the structures compatible with complementary metal-oxide-semiconductor (CMOS) technology applications. Structural studies reveal the self-formation of an Al-rich AlGaAs shell, thicker at the NW base and thinning towards the tip, with the opposite behavior observed for the NW core. Wide alloy fluctuations in the shell region are also noticed. AlGaAs NW structures with nominal Al contents of 10, 20, and 30% have strong room temperature photoluminescence, with emission in the range of 1.50-1.72 eV. Individual NWs with an embedded 4.9 nm-thick GaAs region exhibit clear QD behavior, with spatially localized emission, both exciton and biexciton recombination lines, and an exciton line width of 490 μeV at low temperature. Our results demonstrate the properties and behavior of the AlGaAs NWs and AlGaAs/GaAs NWQDs grown via the self-catalyzed approach for the first time and exhibit their potential for a range of novel applications, including nanolasers and single-photon sources.
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Affiliation(s)
- Giorgos Boras
- Department
of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
| | - Xuezhe Yu
- Department
of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
| | - H. Aruni Fonseka
- Department
of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - George Davis
- Department
of Physics and Astronomy, University of
Sheffield, Sheffield S3 7RH, United Kingdom
| | - Anton V. Velichko
- Department
of Physics and Astronomy, University of
Sheffield, Sheffield S3 7RH, United Kingdom
| | - James A. Gott
- Department
of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Haotian Zeng
- Department
of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
| | - Shiyao Wu
- Institute
of Physics, Chinese Academy of Science, Beijing 100190, China
| | - Patrick Parkinson
- Department
of Physics and Astronomy and the Photon Science Institute, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Xiulai Xu
- Institute
of Physics, Chinese Academy of Science, Beijing 100190, China
| | - David Mowbray
- Department
of Physics and Astronomy, University of
Sheffield, Sheffield S3 7RH, United Kingdom
| | - Ana M. Sanchez
- Department
of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Huiyun Liu
- Department
of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
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8
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Guimbao J, Weituschat LM, Llorens Montolio JM, Postigo PA. Enhancement of the indistinguishability of single photon emitters coupled to photonic waveguides. OPTICS EXPRESS 2021; 29:21160-21173. [PMID: 34265908 DOI: 10.1364/oe.422023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 06/09/2021] [Indexed: 06/13/2023]
Abstract
One of the main steps towards large-scale quantum photonics consists of the integration of single photon sources (SPS) with photonic integrated circuits (PICs). For that purpose, the PICs should offer an efficient light coupling and a high preservation of the indistinguishability of photons. Therefore, optimization of the indistinguishability through waveguide design is especially relevant. In this work we have developed an analytical model that uses the Green's Dyadic of a 3D unbounded rectangular waveguide to calculate the coupling and the indistinguishability of an ideal point-source quantum emitter coupled to a photonic waveguide depending on its orientation and position. The model has been numerically evaluated through finite-difference time-domain (FDTD) simulations showing consistent results. The maximum coupling is achieved when the emitter is embedded in the center of the waveguide but somewhat surprisingly the maximum indistinguishability appears when the emitter is placed at the edge of the waveguide where the electric field is stronger due to the surface discontinuity.
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9
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Gao S, Lazo-Arjona O, Brecht B, Kaczmarek KT, Thomas SE, Nunn J, Ledingham PM, Saunders DJ, Walmsley IA. Optimal Coherent Filtering for Single Noisy Photons. PHYSICAL REVIEW LETTERS 2019; 123:213604. [PMID: 31809170 DOI: 10.1103/physrevlett.123.213604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Indexed: 06/10/2023]
Abstract
We introduce a filter using a noise-free quantum buffer with large optical bandwidth that can both filter temporal-spectral modes as well as interconvert them and change their frequency. We theoretically show that such quantum buffers optimally filter out temporal-spectral noise, producing identical single photons from many distinguishable noisy single-photon sources with the minimum required reduction in brightness. We then experimentally demonstrate a noise-free quantum buffer in a warm atomic system that is well matched to quantum dots. Based on these experiments, simulations show that our buffer can outperform all intensity (incoherent) filtering schemes for increasing indistinguishability.
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Affiliation(s)
- S Gao
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - O Lazo-Arjona
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - B Brecht
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
- Integrated Quantum Optics, Universität Paderborn, Warburger Strasse 100, 33098 Paderborn, Germany
| | - K T Kaczmarek
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
- Groupe de Physique Appliquée, Université de Genève, CH-1211, Genève, Switzerland
| | - S E Thomas
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
- QOLS, Blackett Laboratory, Imperial College London, London SW7 2BW, United Kingdom
| | - J Nunn
- Centre for Photonics and Photonic Materials, Department of Physics, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - P M Ledingham
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - D J Saunders
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - I A Walmsley
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
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10
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Do TN, Khyasudeen MF, Nowakowski PJ, Zhang Z, Tan HS. Measuring Ultrafast Spectral Diffusion and Correlation Dynamics by Two-Dimensional Electronic Spectroscopy. Chem Asian J 2019; 14:3992-4000. [PMID: 31595651 DOI: 10.1002/asia.201900994] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Indexed: 11/07/2022]
Abstract
The frequency fluctuation correlation function (FFCF) measures the spectral diffusion of a state's transition while the frequency fluctuation cross-correlation function (FXCF) measures the correlation dynamics between the transitions of two separate states. These quantities contain a wealth of information on how the chromophores or excitonic states interact and couple with its environment and with each other. We summarize the experimental implementations and theoretical considerations of using two-dimensional electronic spectroscopy to characterize FFCFs and FXCFs. Applications can be found in systems such as the chlorophyll pigment molecules in light-harvesting complexes and CdSe nanomaterials.
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Affiliation(s)
- Thanh Nhut Do
- Disivion of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
| | - M Faisal Khyasudeen
- Disivion of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore.,Department of Chemistry, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Paweł J Nowakowski
- Disivion of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
| | - Zhengyang Zhang
- Disivion of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
| | - Howe-Siang Tan
- Disivion of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
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11
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Lv Y, Yin C, Zhang C, Yu WW, Wang X, Zhang Y, Xiao M. Quantum Interference in a Single Perovskite Nanocrystal. NANO LETTERS 2019; 19:4442-4447. [PMID: 31185175 DOI: 10.1021/acs.nanolett.9b01237] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Coherent manipulation of the exciton wave function in a single semiconductor colloidal nanocrystal (NC) has been actively pursued in the past decades without any success, mainly due to the bothersome existence of the spectral diffusion and the photoluminescence (PL) blinking effects. Such optical deficiencies can be naturally avoided in the newly developed colloidal NCs of perovskite CsPbI3, leading to the PL spectrum with a stable intensity at the single-particle level. Meanwhile, from the first-order photon-correlation measurement, a PL line width smaller than 20 μeV is estimated for the emission state of the neutral exciton in a single CsPbI3 NC. Moreover, a dephasing time of about 10 ps can be extracted from the quantum interference measurement on the absorption state of the charged exciton. This stable demonstration of a coherent optical feature will advance single colloidal NCs into the quantum information regime, opening up an alternative yet prospective research direction beyond their traditional applications such as in optoelectronic devices and bioimaging.
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Affiliation(s)
- Yan Lv
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures , Nanjing University , Nanjing 210093 , China
| | - Chunyang Yin
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures , Nanjing University , Nanjing 210093 , China
| | - Chunfeng Zhang
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures , Nanjing University , Nanjing 210093 , China
| | - William W Yu
- State Key Laboratory of Integrated Optoelectronics, and College of Electronic Science and Engineering , Jilin University , Changchun 130012 , China
| | - Xiaoyong Wang
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures , Nanjing University , Nanjing 210093 , China
| | - Yu Zhang
- State Key Laboratory of Integrated Optoelectronics, and College of Electronic Science and Engineering , Jilin University , Changchun 130012 , China
| | - Min Xiao
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures , Nanjing University , Nanjing 210093 , China
- Department of Physics , University of Arkansas , Fayetteville , Arkansas 72701 , United States
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12
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Dalacu D, Poole PJ, Williams RL. Nanowire-based sources of non-classical light. NANOTECHNOLOGY 2019; 30:232001. [PMID: 30703755 DOI: 10.1088/1361-6528/ab0393] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Sources of quantum light that utilize photonic nanowire designs have emerged as potential candidates for high efficiency non-classical light generation in quantum information processing. In this review we cover the different platforms used to produce nanowire-based sources, highlighting the importance of waveguide design and material properties in achieving optimal performance. The limitations of the sources are identified and routes to optimization are proposed. State-of-the-art nanowire sources are compared to other solid-state quantum emitter platforms with regard to the key metrics of single photon purity, indistinguishability and entangled-pair fidelity to maximally entangled Bell states. We also discuss the unique ability of the nanowire platform to incorporate multiple emitters in the same optical mode and consider potential applications. Finally, routes to on-chip integration are discussed and the challenges facing the development of a nanowire-based scalable architecture are presented.
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Affiliation(s)
- Dan Dalacu
- National Research Council of Canada, Ottawa, Ontario, K1A 0R6, Canada
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13
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Le Roux F, Gao K, Holmes M, Kako S, Arita M, Arakawa Y. Temperature dependence of the single photon emission from interface-fluctuation GaN quantum dots. Sci Rep 2017; 7:16107. [PMID: 29170385 PMCID: PMC5700965 DOI: 10.1038/s41598-017-16040-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 11/06/2017] [Indexed: 11/23/2022] Open
Abstract
The temperature dependent single photon emission statistics of interface-fluctuation GaN quantum dots are reported. Quantum light emission is confirmed at temperatures up to ~77 K, by which point the background emission degrades the emission purity and results in a measured g(2) (0) in excess of 0.5. A discussion on the extent of the background contamination is also given through comparison to extensive data taken under various ambient and experimental conditions, revealing that the quantum dots themselves are emitting single photons with high purity.
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Affiliation(s)
- F Le Roux
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan
| | | | - M Holmes
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan. .,Institute for Nano Quantum Information Electronics, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan.
| | - S Kako
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan.,Institute for Nano Quantum Information Electronics, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan
| | - M Arita
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan.,Institute for Nano Quantum Information Electronics, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan
| | - Y Arakawa
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan. .,Institute for Nano Quantum Information Electronics, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan.
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14
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Senellart P, Solomon G, White A. High-performance semiconductor quantum-dot single-photon sources. NATURE NANOTECHNOLOGY 2017; 12:1026-1039. [PMID: 29109549 DOI: 10.1038/nnano.2017.218] [Citation(s) in RCA: 247] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 09/29/2017] [Indexed: 05/20/2023]
Abstract
Single photons are a fundamental element of most quantum optical technologies. The ideal single-photon source is an on-demand, deterministic, single-photon source delivering light pulses in a well-defined polarization and spatiotemporal mode, and containing exactly one photon. In addition, for many applications, there is a quantum advantage if the single photons are indistinguishable in all their degrees of freedom. Single-photon sources based on parametric down-conversion are currently used, and while excellent in many ways, scaling to large quantum optical systems remains challenging. In 2000, semiconductor quantum dots were shown to emit single photons, opening a path towards integrated single-photon sources. Here, we review the progress achieved in the past few years, and discuss remaining challenges. The latest quantum dot-based single-photon sources are edging closer to the ideal single-photon source, and have opened new possibilities for quantum technologies.
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Affiliation(s)
- Pascale Senellart
- Center for Nanosciences and Nanotechnology CNRS, UMR9001, University Paris-Saclay, C2N - Site de Marcoussis, Route de Nozay, 91460 Marcoussis, France
| | - Glenn Solomon
- Joint Quantum Institute, National Institute of Standards and Technology, and University of Maryland, Gaithersburg, Maryland 20889, USA
| | - Andrew White
- Centre for Engineered Quantum Systems and Centre for Quantum Computer and Communication Technology, School of Mathematics and Physics, University of Queensland, Brisbane, Queensland 4072, Australia
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15
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Brehm M, Grydlik M. Site-controlled and advanced epitaxial Ge/Si quantum dots: fabrication, properties, and applications. NANOTECHNOLOGY 2017; 28:392001. [PMID: 28729522 DOI: 10.1088/1361-6528/aa8143] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In this review, we report on fabrication paths, challenges, and emerging solutions to integrate group-IV epitaxial quantum dots (QDs) as active light emitters into the existing standard Si technology. Their potential as laser gain material for the use of optical intra- and inter-chip interconnects as well as possibilities to combine a single-photon-source-based quantum cryptographic means with Si technology will be discussed. We propose that the mandatory addressability of the light emitters can be achieved by a combination of organized QD growth assisted by templated self-assembly, and advanced inter-QD defect engineering to boost the optical emissivity of group-IV QDs at room-temperature. Those two main parts, the site-controlled growth and the light emission enhancement in QDs through the introduction of single defects build the main body of the review. This leads us to a roadmap for the necessary further development of this emerging field of CMOS-compatible group-IV QD light emitters for on-chip applications.
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16
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Moody G, Cundiff ST. Advances in multi-dimensional coherent spectroscopy of semiconductor nanostructures. ADVANCES IN PHYSICS: X 2017; 2:641-674. [PMID: 28894306 PMCID: PMC5590666 DOI: 10.1080/23746149.2017.1346482] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023] Open
Abstract
Multi-dimensional coherent spectroscopy (MDCS) has become an extremely versatile and sensitive technique for elucidating the structure, composition, and dynamics of condensed matter, atomic, and molecular systems. The appeal of MDCS lies in its ability to resolve both individual-emitter and ensemble-averaged dynamics of optically created excitations in disordered systems. When applied to semiconductors, MDCS enables unambiguous separation of homogeneous and inhomogeneous contributions to the optical linewidth, pinpoints the nature of coupling between resonances, and reveals signatures of many-body interactions. In this review, we discuss the implementation of MDCS to measure the nonlinear optical response of excitonic transitions in semiconductor nanostructures. Capabilities of the technique are illustrated with recent experimental studies that advance our understanding of optical decoherence and dissipation, energy transfer, and many-body phenomena in quantum dots and quantum wells, semiconductor microcavities, layered semiconductors, and photovoltaic materials.
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Affiliation(s)
- Galan Moody
- Applied Physics Division, National Institute of Standards & Technology, Boulder, CO, USA
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17
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Tighineanu P, Daveau RS, Lehmann TB, Beere HE, Ritchie DA, Lodahl P, Stobbe S. Single-Photon Superradiance from a Quantum Dot. PHYSICAL REVIEW LETTERS 2016; 116:163604. [PMID: 27152804 DOI: 10.1103/physrevlett.116.163604] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Indexed: 06/05/2023]
Abstract
We report on the observation of single-photon superradiance from an exciton in a semiconductor quantum dot. The confinement by the quantum dot is strong enough for it to mimic a two-level atom, yet sufficiently weak to ensure superradiance. The electrostatic interaction between the electron and the hole comprising the exciton gives rise to an anharmonic spectrum, which we exploit to prepare the superradiant quantum state deterministically with a laser pulse. We observe a fivefold enhancement of the oscillator strength compared to conventional quantum dots. The enhancement is limited by the base temperature of our cryostat and may lead to oscillator strengths above 1000 from a single quantum emitter at optical frequencies.
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Affiliation(s)
- Petru Tighineanu
- Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, DK-2100 Copenhagen, Denmark
| | - Raphaël S Daveau
- Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, DK-2100 Copenhagen, Denmark
| | - Tau B Lehmann
- Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, DK-2100 Copenhagen, Denmark
| | - Harvey E Beere
- Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, CB3 0HE Cambridge, United Kingdom
| | - David A Ritchie
- Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, CB3 0HE Cambridge, United Kingdom
| | - Peter Lodahl
- Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, DK-2100 Copenhagen, Denmark
| | - Søren Stobbe
- Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, DK-2100 Copenhagen, Denmark
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18
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Srivastava A, Sidler M, Allain AV, Lembke DS, Kis A, Imamoğlu A. Optically active quantum dots in monolayer WSe2. NATURE NANOTECHNOLOGY 2015; 10:491-6. [PMID: 25938570 DOI: 10.1038/nnano.2015.60] [Citation(s) in RCA: 310] [Impact Index Per Article: 34.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 03/04/2015] [Indexed: 05/20/2023]
Abstract
Semiconductor quantum dots have emerged as promising candidates for the implementation of quantum information processing, because they allow for a quantum interface between stationary spin qubits and propagating single photons. In the meantime, transition-metal dichalcogenide monolayers have moved to the forefront of solid-state research due to their unique band structure featuring a large bandgap with degenerate valleys and non-zero Berry curvature. Here, we report the observation of zero-dimensional anharmonic quantum emitters, which we refer to as quantum dots, in monolayer tungsten diselenide, with an energy that is 20-100 meV lower than that of two-dimensional excitons. Photon antibunching in second-order photon correlations unequivocally demonstrates the zero-dimensional anharmonic nature of these quantum emitters. The strong anisotropic magnetic response of the spatially localized emission peaks strongly indicates that radiative recombination stems from localized excitons that inherit their electronic properties from the host transition-metal dichalcogenide. The large ∼1 meV zero-field splitting shows that the quantum dots have singlet ground states and an anisotropic confinement that is most probably induced by impurities or defects. The possibility of achieving electrical control in van der Waals heterostructures and to exploit the spin-valley degree of freedom renders transition-metal-dichalcogenide quantum dots interesting for quantum information processing.
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Affiliation(s)
- Ajit Srivastava
- Institute of Quantum Electronics, ETH Zurich, Zurich CH-8093, Switzerland
| | - Meinrad Sidler
- Institute of Quantum Electronics, ETH Zurich, Zurich CH-8093, Switzerland
| | - Adrien V Allain
- Electrical Engineering Institute, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015, Switzerland
| | - Dominik S Lembke
- Electrical Engineering Institute, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015, Switzerland
| | - Andras Kis
- Electrical Engineering Institute, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015, Switzerland
| | - A Imamoğlu
- Institute of Quantum Electronics, ETH Zurich, Zurich CH-8093, Switzerland
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19
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Shi T, Jackson HE, Smith LM, Jiang N, Gao Q, Tan HH, Jagadish C, Zheng C, Etheridge J. Emergence of localized states in narrow GaAs/AlGaAs nanowire quantum well tubes. NANO LETTERS 2015; 15:1876-1882. [PMID: 25714336 DOI: 10.1021/nl5046878] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We use low-temperature photoluminescence, photoluminescence excitation, and photoluminescence imaging spectroscopy to explore the optical and electronic properties of GaAs/AlGaAs quantum well tube (QWT) heterostructured nanowires (NWs). We find that GaAs QWTs with widths >5 nm have electronic states which are delocalized and continuous along the length of the NW. As the NW QWT width decreases from 5 to 1.5 nm, only a single electron state is bound to the well, and no optical excitations to a confined excited state are present. Simultaneously, narrow emission lines (fwhm < 600 μeV) appear which are localized to single spatial points along the length of the NW. We find that these quantum-dot-like states broaden at higher temperatures and quench at temperatures above 80 K. The lifetimes of these localized states are observed to vary from dot to dot from 160 to 400 ps. The presence of delocalized states and then localized states as the QWTs become more confined suggests both opportunities and challenges for possible incorporation into quantum-confined device structures.
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Affiliation(s)
- Teng Shi
- Department of Physics, University of Cincinnati , Cincinnati, Ohio 45221-0011, United States
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20
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Kim S, Lee K, Kim S, Kwon OP, Heo JH, Im SH, Jeong S, Lee DC, Kim SW. Origin of photoluminescence from colloidal gallium phosphide nanocrystals synthesized via a hot-injection method. RSC Adv 2015. [DOI: 10.1039/c4ra10115d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The emission and excitation spectra of the GaP NCs indicate that two transitions, near the direct and indirect bandgaps of bulk GaP, are responsible for the luminescence.
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Affiliation(s)
- Sungwoo Kim
- Department of Molecular Science and Technology
- Ajou University
- Suwon 443-749
- Republic of Korea
- Nanomechanical Systems Research Division
| | - Kangha Lee
- Department of Chemical and Biomolecular Engineering
- KAIST Institute for the Nanocentury (KINC)
- Korea Advanced Institute of Science and Technology (KAIST)
- Daejeon 305-701
- Republic of Korea
| | - Sejin Kim
- Department of Molecular Science and Technology
- Ajou University
- Suwon 443-749
- Republic of Korea
| | - O.-Pil Kwon
- Department of Molecular Science and Technology
- Ajou University
- Suwon 443-749
- Republic of Korea
| | - Jin Hyuk Heo
- Department of Chemical Engineering
- College of Engineering
- Kyung Hee University
- Gyeonggi-do 446-701
- Republic of Korea
| | - Sang Hyuk Im
- Department of Chemical Engineering
- College of Engineering
- Kyung Hee University
- Gyeonggi-do 446-701
- Republic of Korea
| | - Sohee Jeong
- Nanomechanical Systems Research Division
- Korea Institute of Machinery and Materials
- Daejeon 305-343
- Republic of Korea
| | - Doh C. Lee
- Department of Chemical and Biomolecular Engineering
- KAIST Institute for the Nanocentury (KINC)
- Korea Advanced Institute of Science and Technology (KAIST)
- Daejeon 305-701
- Republic of Korea
| | - Sang-Wook Kim
- Department of Molecular Science and Technology
- Ajou University
- Suwon 443-749
- Republic of Korea
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21
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Yang L, Glasenapp P, Greilich A, Reuter D, Wieck AD, Yakovlev DR, Bayer M, Crooker SA. Two-colour spin noise spectroscopy and fluctuation correlations reveal homogeneous linewidths within quantum-dot ensembles. Nat Commun 2014; 5:4949. [DOI: 10.1038/ncomms5949] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 08/09/2014] [Indexed: 11/09/2022] Open
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22
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Chusseau L, Philippe F, Disanto F. Monte Carlo modeling of the dual-mode regime in quantum-well and quantum-dot semiconductor lasers. OPTICS EXPRESS 2014; 22:5312-5324. [PMID: 24663872 DOI: 10.1364/oe.22.005312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Monte Carlo markovian models of a dual-mode semiconductor laser with quantum well (QW) or quantum dot (QD) active regions are proposed. Accounting for carriers and photons as particles that may exchange energy in the course of time allows an ab initio description of laser dynamics such as the mode competition and intrinsic laser noise. We used these models to evaluate the stability of the dual-mode regime when laser characteristics are varied: mode gains and losses, non-radiative recombination rates, intraband relaxation time, capture time in QD, transfer of excitation between QD via the wetting layer... As a major result, a possible steady-state dual-mode regime is predicted for specially designed QD semiconductor lasers thereby acting as a CW microwave or terahertz-beating source whereas it does not occur for QW lasers.
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23
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Trotta R, Zallo E, Ortix C, Atkinson P, Plumhof JD, van den Brink J, Rastelli A, Schmidt OG. Universal recovery of the energy-level degeneracy of bright excitons in InGaAs quantum dots without a structure symmetry. PHYSICAL REVIEW LETTERS 2012; 109:147401. [PMID: 23083282 DOI: 10.1103/physrevlett.109.147401] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Indexed: 06/01/2023]
Abstract
The lack of structural symmetry which usually characterizes semiconductor quantum dots lifts the energetic degeneracy of the bright excitonic states and hampers severely their use as high-fidelity sources of entangled photons. We demonstrate experimentally and theoretically that it is always possible to restore the excitonic degeneracy by the simultaneous application of large strain and electric fields. This is achieved by using one external perturbation to align the polarization of the exciton emission along the axis of the second perturbation, which then erases completely the energy splitting of the states. This result, which holds for any quantum dot structure, highlights the potential of combining complementary external fields to create artificial atoms meeting the stringent requirements posed by scalable semiconductor-based quantum technology.
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Affiliation(s)
- R Trotta
- Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany.
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24
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Lo SS, Major TA, Petchsang N, Huang L, Kuno MK, Hartland GV. Charge carrier trapping and acoustic phonon modes in single CdTe nanowires. ACS NANO 2012; 6:5274-5282. [PMID: 22559050 DOI: 10.1021/nn3010526] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Semiconductor nanostructures produced by wet chemical synthesis are extremely heterogeneous, which makes single particle techniques a useful way to interrogate their properties. In this paper the ultrafast dynamics of single CdTe nanowires are studied by transient absorption microscopy. The wires have lengths of several micrometers and lateral dimensions on the order of 30 nm. The transient absorption traces show very fast decays, which are assigned to charge carrier trapping into surface defects. The time constants vary for different wires due to differences in the energetics and/or density of surface trap sites. Measurements performed at the band edge compared to the near-IR give slightly different time constants, implying that the dynamics for electron and hole trapping are different. The rate of charge carrier trapping was observed to slow down at high carrier densities, which was attributed to trap-state filling. Modulations due to the fundamental and first overtone of the acoustic breathing mode were also observed in the transient absorption traces. The quality factors for these modes were similar to those measured for metal nanostructures, and indicate a complex interaction with the environment.
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Affiliation(s)
- Shun Shang Lo
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556-5670, USA
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25
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Ghali M, Ohtani K, Ohno Y, Ohno H. Generation and control of polarization-entangled photons from GaAs island quantum dots by an electric field. Nat Commun 2012; 3:661. [PMID: 22314357 PMCID: PMC3293408 DOI: 10.1038/ncomms1657] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 12/21/2011] [Indexed: 11/09/2022] Open
Abstract
Semiconductor quantum dots are potential sources for generating polarization-entangled photons efficiently. The main prerequisite for such generation based on biexciton-exciton cascaded emission is to control the exciton fine-structure splitting. Among various techniques investigated for this purpose, an electric field is a promising means to facilitate the integration into optoelectronic devices. Here we demonstrate the generation of polarization-entangled photons from single GaAs quantum dots by an electric field. In contrast to previous studies, which were limited to In(Ga)As quantum dots, GaAs island quantum dots formed by a thickness fluctuation were used because they exhibit a larger oscillator strength and emit light with a shorter wavelength. A forward voltage was applied to a Schottky diode to control the fine-structure splitting. We observed a decrease and suppression in the fine-structure splitting of the studied single quantum dot with the field, which enabled us to generate polarization-entangled photons with a high fidelity of 0.72 ± 0.05.
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Affiliation(s)
- Mohsen Ghali
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
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26
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Maruccio G, Wiesendanger R. Scanning Tunneling Spectroscopy of Semiconductor Quantum Dots and Nanocrystals. ACTA ACUST UNITED AC 2010. [DOI: 10.1007/978-3-642-10553-1_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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27
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Huxter VM, Scholes GD. Acoustic phonon strain induced mixing of the fine structure levels in colloidal CdSe quantum dots observed by a polarization grating technique. J Chem Phys 2010; 132:104506. [DOI: 10.1063/1.3350871] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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28
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Flagg EB, Robertson JW, Founta S, Ma W, Xiao M, Salamo GJ, Shih CK. Direct evidence of interlevel exciton transitions mediated by single phonons in a semiconductor quantum dot using resonance fluorescence spectroscopy. PHYSICAL REVIEW LETTERS 2009; 102:097402. [PMID: 19392564 DOI: 10.1103/physrevlett.102.097402] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2008] [Indexed: 05/27/2023]
Abstract
Using resonance fluorescence, we investigate how acoustic phonons mediate couplings between multiple electronic levels in a semiconductor quantum dot. We show the first direct evidence of population up-conversion in a single quantum dot, which we attribute to absorption of single acoustic phonons. Moreover, through a rate equation analysis, we find that below 20 K such single-phonon mediated couplings between the exciton ground state and the first excited state are primarily responsible for decoherence of the exciton quantum state.
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Affiliation(s)
- Edward B Flagg
- Physics Department, University of Texas at Austin, 1 University Station C1600, Austin, Texas 78712, USA.
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29
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Wu Y, Kim ED, Xu X, Cheng J, Steel DG, Bracker AS, Gammon D, Economou SE, Sham LJ. Selective optical control of electron spin coherence in singly charged GaAs-Al0.3Ga0.7As quantum dots. PHYSICAL REVIEW LETTERS 2007; 99:097402. [PMID: 17931036 DOI: 10.1103/physrevlett.99.097402] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2007] [Indexed: 05/25/2023]
Abstract
Coherent transient excitation of the spin ground states in singly charged quantum dots creates optically coupled and decoupled states of the electron spin. We demonstrate selective excitation from the spin ground states to the trion state through phase sensitive control of the spin coherence via these three states, leading to partial rotations of the spin vector. This progress lays the ground work for achieving complete ultrafast spin rotations.
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Affiliation(s)
- Yanwen Wu
- The H. M. Randall Laboratory of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA
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30
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Clark SM, Fu KMC, Ladd TD, Yamamoto Y. Quantum computers based on electron spins controlled by ultrafast off-resonant single optical pulses. PHYSICAL REVIEW LETTERS 2007; 99:040501. [PMID: 17678343 DOI: 10.1103/physrevlett.99.040501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2006] [Revised: 05/13/2007] [Indexed: 05/16/2023]
Abstract
We describe a fast quantum computer based on optically controlled electron spins in charged quantum dots that are coupled to microcavities. This scheme uses broadband optical pulses to rotate electron spins and provide the clock signal to the system. Nonlocal two-qubit gates are performed by phase shifts induced by electron spins on laser pulses propagating along a shared waveguide. Numerical simulations of this scheme demonstrate high-fidelity single-qubit and two-qubit gates with operation times comparable to the inverse Zeeman frequency.
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Affiliation(s)
- Susan M Clark
- Edward L. Ginzton Laboratory, Stanford University, Stanford, California 94305-4088, USA.
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31
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Dai Q, Song Y, Li D, Chen H, Kan S, Zou B, Wang Y, Deng Y, Hou Y, Yu S, Chen L, Liu B, Zou G. Temperature dependence of band gap in CdSe nanocrystals. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2007.03.034] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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32
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Salvador MR, Graham MW, Scholes GD. Exciton-phonon coupling and disorder in the excited states of CdSe colloidal quantum dots. J Chem Phys 2006; 125:184709. [PMID: 17115781 DOI: 10.1063/1.2363190] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We study the origin of the spectral line shape in colloidal CdSe nanocrystal quantum dots. The three-pulse photon echo peak shift (3PEPS) data reveal a temperature-independent fast decay, obscuring the quantification of the homogeneous linewidth. The optical gap and Stokes shift are found to have an anomalous behavior with temperature, which is size, capping group, and surrounding polymer matrix independent. Using these results and combining them with simulations, we discuss the role of exciton-phonon coupling, static inhomogeneity, exciton fine structure, and exciton state disorder in the linewidth of the nanocrystal. In particular, our analysis shows that the disorder due to surface imperfections and finite temperature effects, as well as the relaxation within the fine structure, can have significant impact on the steady-state absorption spectrum, 3PEPS data, and dephasing processes.
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Affiliation(s)
- Mayrose R Salvador
- Lash-Miller Chemical Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
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33
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Berezovsky J, Mikkelsen MH, Gywat O, Stoltz NG, Coldren LA, Awschalom DD. Nondestructive Optical Measurements of a Single Electron Spin in a Quantum Dot. Science 2006; 314:1916-20. [PMID: 17095655 DOI: 10.1126/science.1133862] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Kerr rotation measurements on a single electron spin confined in a charge-tunable semiconductor quantum dot demonstrate a means to directly probe the spin off-resonance, thus minimally disturbing the system. Energy-resolved magneto-optical spectra reveal information about the optically oriented spin polarization and the transverse spin lifetime of the electron as a function of the charging of the dot. These results represent progress toward the manipulation and coupling of single spins and photons for quantum information processing.
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Affiliation(s)
- J Berezovsky
- Center for Spintronics and Quantum Computation, University of California, Santa Barbara, CA 93106, USA
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34
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Gershoni D. Quantum information: long live the spin. NATURE MATERIALS 2006; 5:255-6. [PMID: 16582925 DOI: 10.1038/nmat1620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
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35
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Borri P, Schneider S, Langbein W, Bimberg D. Ultrafast carrier dynamics in InGaAs quantum dot materials and devices. ACTA ACUST UNITED AC 2006. [DOI: 10.1088/1464-4258/8/4/s03] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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36
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Wu Y, Li X, Duan LM, Steel DG, Gammon D. Density matrix tomography through sequential coherent optical rotations of an exciton qubit in a single quantum dot. PHYSICAL REVIEW LETTERS 2006; 96:087402. [PMID: 16606223 DOI: 10.1103/physrevlett.96.087402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2005] [Indexed: 05/08/2023]
Abstract
We demonstrate single qubit density matrix tomography in a single semiconductor quantum dot system through consecutive phase sensitive rotations of the qubit via ultrafast coherent optical excitations. The result is important for quantifying gate operations in quantum information processing in the quantum dot systems as well as demonstrating consecutive arbitrary qubit rotations.
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Affiliation(s)
- Yanwen Wu
- The H.M. Randall Laboratory of Physics, The University of Michigan, Ann Arbor, Michigan 48109, USA
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39
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Zhao H, Dal Don B, Schwartz G, Kalt H. Ultrafast breathinglike oscillation in the exciton density of ZnSe quantum wells. PHYSICAL REVIEW LETTERS 2005; 94:137402. [PMID: 15904033 DOI: 10.1103/physrevlett.94.137402] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2004] [Indexed: 05/02/2023]
Abstract
The spatial density profile of a low-density exciton ensemble in ZnSe quantum wells shows a breathinglike oscillation on a 30-ps time scale. This breathing results from the emission of the first acoustic phonon at the end of the quasiballistic transport phase of the excitons which reverses their direction of propagation. Since the scattering destroys the phase of the excitonic wave function, one can deduce simultaneously the coherence length and the coherence time of excitonic transport by evaluation of the oscillation measured from a single experiment. The breathing, which can be modeled by Monte Carlo simulations, is quenched for rising lattice temperature, i.e., increasing phonon absorption, and in samples with significant disorder. These results were obtained by time-resolved nanophotoluminescence with 5 ps and 250 nm temporal and spatial resolution, respectively.
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Affiliation(s)
- Hui Zhao
- Institut für Angewandte Physik, Universität Karlsruhe, D-76128 Karlsruhe, Germany
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40
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Müller J, Lupton JM, Rogach AL, Feldmann J, Talapin DV, Weller H. Monitoring surface charge movement in single elongated semiconductor nanocrystals. PHYSICAL REVIEW LETTERS 2004; 93:167402. [PMID: 15525031 DOI: 10.1103/physrevlett.93.167402] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2004] [Indexed: 05/24/2023]
Abstract
We demonstrate a universal correlation between the spectral linewidth and position of the excitonic transition in the spectral jitter observed from single elongated colloidal quantum dots. Breaking the symmetry of electron and hole confinement as well as of the spatial directions for surface charge diffusion enables us to microscopically track meandering surface charges, providing a novel probe of the particle's nanoenvironment. Spectral diffusion exhibits only a weak temperature dependence, which allows us to uncover the single particle homogeneous linewidth of 50 meV at room temperature.
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Affiliation(s)
- J Müller
- Photonics and Optoelectronics Group, Physics Department and CeNS, Ludwig-Maximilians-Universität, Amalienstrasse 54, 80799 München, Germany
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41
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Lienau C. Ultrafast near-field spectroscopy of single semiconductor quantum dots. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2004; 362:861-879. [PMID: 15306498 DOI: 10.1098/rsta.2003.1353] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Excitonic and spin excitations of single semiconductor quantum dots (QDs) currently attract attention as possible candidates for solid-state-based implementations of quantum logic devices. Due to their rather short decoherence times in the picosecond to nanosecond range, such implementations rely on using ultrafast optical pulses to probe and control coherent polarizations. We combine ultrafast spectroscopy and near-field microscopy to probe the nonlinear optical response of a single QD on a femtosecond time-scale. Transient reflectivity spectra show pronounced oscillations around the QD exciton line. These oscillations reflect phase-disturbing Coulomb interactions between the excitonic QD polarization and continuum excitations. The results show that although semiconductor QDs resemble in many respects atomic systems, Coulomb many-body interactions can contribute significantly to their optical nonlinearities on ultrashort time-scales.
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Affiliation(s)
- Christoph Lienau
- Max-Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max Born Strasse 2A, 12489 Berlin, Germany.
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42
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Karrai K, Warburton RJ, Schulhauser C, Högele A, Urbaszek B, McGhee EJ, Govorov AO, Garcia JM, Gerardot BD, Petroff PM. Hybridization of electronic states in quantum dots through photon emission. Nature 2004; 427:135-8. [PMID: 14712271 DOI: 10.1038/nature02109] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2003] [Accepted: 10/02/2003] [Indexed: 11/08/2022]
Abstract
The self-assembly of semiconductor quantum dots has opened up new opportunities in photonics. Quantum dots are usually described as 'artificial atoms', because electron and hole confinement gives rise to discrete energy levels. This picture can be justified from the shell structure observed as a quantum dot is filled either with excitons (bound electron-hole pairs) or with electrons. The discrete energy levels have been most spectacularly exploited in single photon sources that use a single quantum dot as emitter. At low temperatures, the artificial atom picture is strengthened by the long coherence times of excitons in quantum dots, motivating the application of quantum dots in quantum optics and quantum information processing. In this context, excitons in quantum dots have already been manipulated coherently. We show here that quantum dots can also possess electronic states that go far beyond the artificial atom model. These states are a coherent hybridization of localized quantum dot states and extended continuum states: they have no analogue in atomic physics. The states are generated by the emission of a photon from a quantum dot. We show how a new version of the Anderson model that describes interactions between localized and extended states can account for the observed hybridization.
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Affiliation(s)
- Khaled Karrai
- Center for NanoScience and Sektion Physik, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, 80539 München, Germany
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43
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Halsall MP, Harmer P, Parbrook PJ, Wang T, Wells JR. Photoluminescence of single InGaN quantum dots grown at low surface densities by MOVPE. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/pssc.200303525] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
| | - P. Harmer
- Department of Physics UMIST, P.O. Box 88, Manchester, M60 1QD, UK
| | - P. J. Parbrook
- EPSRC National Centre for III–V Technologies, Department of Electronic and Electrical Engineering, Mappin Street, Sheffield, S1 3JD, UK
| | - T. Wang
- EPSRC National Centre for III–V Technologies, Department of Electronic and Electrical Engineering, Mappin Street, Sheffield, S1 3JD, UK
| | - J.‐P. R. Wells
- Department of Physics and Astronomy, University of Sheffield, S3 7RH, UK
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44
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Li X, Wu Y, Steel D, Gammon D, Stievater TH, Katzer DS, Park D, Piermarocchi C, Sham LJ. An all-optical quantum gate in a semiconductor quantum dot. Science 2003; 301:809-11. [PMID: 12907794 DOI: 10.1126/science.1083800] [Citation(s) in RCA: 188] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We report coherent optical control of a biexciton (two electron-hole pairs), confined in a single quantum dot, that shows coherent oscillations similar to the excited-state Rabi flopping in an isolated atom. The pulse control of the biexciton dynamics, combined with previously demonstrated control of the single-exciton Rabi rotation, serves as the physical basis for a two-bit conditional quantum logic gate. The truth table of the gate shows the features of an all-optical quantum gate with interacting yet distinguishable excitons as qubits. Evaluation of the fidelity yields a value of 0.7 for the gate operation. Such experimental capability is essential to a scheme for scalable quantum computation by means of the optical control of spin qubits in dots.
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Affiliation(s)
- Xiaoqin Li
- Frontiers in Optical Coherent and Ultrafast Science (FOCUS), Harrison M. Randall Laboratory of Physics, The University of Michigan, Ann Arbor, Michigan 48109-1120, USA
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45
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Kazantsev DV, Dal Savio C, Pierz K, Güttler B, Danzebrink HU. Low-temperature scanning system for near- and far-field optical investigations. J Microsc 2003; 209:199-204. [PMID: 12641762 DOI: 10.1046/j.1365-2818.2003.01114.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A combined system for far- and near-field optical spectroscopy consisting of a compact scanning near-field optical microscope and a dedicated spectrometer was realized. The set-up allows the optical investigation of samples at temperatures from 10 to 300 K. The sample positioning range is as large as 5 x 5 x 5 mm3 and the spatial resolution is in the range of 1.5 micro m in the far-field optical microscopy mode at low temperatures. In the scanning near-field optical microscope mode the resolution is defined by the microfabricated cantilever probe, which is placed in the focus of a double-mirror objective. The tip-to-sample distance in the scanning near-field optical microscope is controlled by a beam deflection system in dynamic scanning force microscopy mode. After a description of the apparatus, scanning force topography images of self-assembled InAs quantum dots on a GaAs substrate with a density of less than one dot per square micrometre are shown, followed by the first spectroscopic investigations of such a sample. The presented results demonstrate the potential of the system.
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Affiliation(s)
- D V Kazantsev
- Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig, Germany
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46
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Kiraz A, Reese C, Gayral B, Zhang L, Schoenfeld WV, Gerardot BD, Petroff PM, Hu EL, Imamoglu A. Cavity-quantum electrodynamics with quantum dots. ACTA ACUST UNITED AC 2003. [DOI: 10.1088/1464-4266/5/2/303] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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47
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Santori C, Fattal D, Vucković J, Solomon GS, Yamamoto Y. Indistinguishable photons from a single-photon device. Nature 2002; 419:594-7. [PMID: 12374958 DOI: 10.1038/nature01086] [Citation(s) in RCA: 347] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Single-photon sources have recently been demonstrated using a variety of devices, including molecules, mesoscopic quantum wells, colour centres, trapped ions and semiconductor quantum dots. Compared with a Poisson-distributed source of the same intensity, these sources rarely emit two or more photons in the same pulse. Numerous applications for single-photon sources have been proposed in the field of quantum information, but most--including linear-optical quantum computation--also require consecutive photons to have identical wave packets. For a source based on a single quantum emitter, the emitter must therefore be excited in a rapid or deterministic way, and interact little with its surrounding environment. Here we test the indistinguishability of photons emitted by a semiconductor quantum dot in a microcavity through a Hong-Ou-Mandel-type two-photon interference experiment. We find that consecutive photons are largely indistinguishable, with a mean wave-packet overlap as large as 0.81, making this source useful in a variety of experiments in quantum optics and quantum information.
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Affiliation(s)
- Charles Santori
- Quantum Entanglement Project, ICORP, JST, E. L. Ginzton Laboratory, Stanford University, Stanford, California 94305-4088, USA.
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48
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Zhao H, Moehl S, Kalt H. Coherence length of excitons in a semiconductor quantum well. PHYSICAL REVIEW LETTERS 2002; 89:097401. [PMID: 12190436 DOI: 10.1103/physrevlett.89.097401] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2002] [Indexed: 05/23/2023]
Abstract
We report on the first experimental determination of the coherence length of excitons in semiconductors using the combination of spatially resolved photoluminescence with phonon sideband spectroscopy. The coherence length of excitons in ZnSe quantum wells is determined to be 300-400 nm, about 25-30 times the exciton de Broglie wavelength. With increasing exciton kinetic energy, the coherence length decreases slowly. The discrepancy between the coherence lengths measured and calculated by considering only the acoustic-phonon scattering suggests an important influence of static disorder.
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Affiliation(s)
- Hui Zhao
- Institut für Angewandte Physik, Universität Karlsruhe, D-76128 Karlsruhe, Germany
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49
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Steffan A, Phillips R. Exciton g-Factors, Diamagnetic Shifts, and Exchange Splittings in Quantum Dots in GaAs Quantum Wells. ACTA ACUST UNITED AC 2002. [DOI: 10.1002/1521-396x(200204)190:2<541::aid-pssa541>3.0.co;2-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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50
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Chen G, Stievater TH, Batteh ET, Li X, Steel DG, Gammon D, Katzer DS, Park D, Sham LJ. Biexciton quantum coherence in a single quantum dot. PHYSICAL REVIEW LETTERS 2002; 88:117901. [PMID: 11909428 DOI: 10.1103/physrevlett.88.117901] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2001] [Indexed: 05/23/2023]
Abstract
Nondegenerate (two-wavelength) two-photon absorption using coherent optical fields is used to show that there are two different quantum mechanical pathways leading to formation of the biexciton in a single quantum dot. Of specific importance to quantum information applications is the resulting coherent dynamics between the ground state and the biexciton from the pathway involving only optically induced exciton/biexciton quantum coherence. The data provide a direct measure of the biexciton decoherence rate which is equivalent to the decoherence of the Bell state in this system, as well as other critical optical parameters.
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Affiliation(s)
- Gang Chen
- The FOCUS Center, Harrison M. Randall Laboratory, University of Michigan, Ann Arbor, Michigan 48109, USA
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