1
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Li D, Radhakrishnan R, Akopian N. Location Qubits in a Multiple-Quantum-Dot System. NANO LETTERS 2024; 24:5656-5661. [PMID: 38657275 DOI: 10.1021/acs.nanolett.4c01272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
A physical platform for nodes of the envisioned quantum Internet is long-sought. Here we propose such a platform, along with a conceptually simple and experimentally uncomplicated quantum information processing scheme, realized in a system of multiple crystal-phase quantum dots. We introduce novel location qubits, describe a method to construct a universal set of all-optical quantum gates, and simulate their performance in realistic structures, including decoherence sources. Our results show that location qubits are robust against the main decoherence mechanisms, and realistic single-qubit gate fidelities exceed 99.9%. Our scheme paves a clear way toward constructing multiqubit solid-state quantum registers with a built-in photonic interface─a key building block of the forthcoming quantum Internet.
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Affiliation(s)
- Dayang Li
- DTU Department of Electrical and Photonics Engineering, Technical University of Denmark, Ørsteds Plads Building 343, 2800 Kongens Lyngby, Denmark
| | - Rohan Radhakrishnan
- DTU Department of Electrical and Photonics Engineering, Technical University of Denmark, Ørsteds Plads Building 343, 2800 Kongens Lyngby, Denmark
| | - Nika Akopian
- DTU Department of Electrical and Photonics Engineering, Technical University of Denmark, Ørsteds Plads Building 343, 2800 Kongens Lyngby, Denmark
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2
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Barettin D. State of the Art of Continuous and Atomistic Modeling of Electromechanical Properties of Semiconductor Quantum Dots. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:1820. [PMID: 37368250 DOI: 10.3390/nano13121820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 06/05/2023] [Accepted: 06/05/2023] [Indexed: 06/28/2023]
Abstract
The main intent of this paper is to present an exhaustive description of the most relevant mathematical models for the electromechanical properties of heterostructure quantum dots. Models are applied both to wurtzite and zincblende quantum dot due to the relevance they have shown for optoelectronic applications. In addition to a complete overview of the continuous and atomistic models for the electromechanical fields, analytical results will be presented for some relevant approximations, some of which are unpublished, such as models in cylindrical approximation or a cubic approximation for the transformation of a zincblende parametrization to a wurtzite one and vice versa. All analytical models will be supported by a wide range of numerical results, most of which are also compared with experimental measurements.
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Affiliation(s)
- Daniele Barettin
- Daniele Barettin of Electronic Engineering, Università Niccoló Cusano, 00133 Rome, Italy
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3
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Schmiedeke P, Panciera F, Harmand JC, Travers L, Koblmüller G. Real-time thermal decomposition kinetics of GaAs nanowires and their crystal polytypes on the atomic scale. NANOSCALE ADVANCES 2023; 5:2994-3004. [PMID: 37260482 PMCID: PMC10228496 DOI: 10.1039/d3na00135k] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 05/02/2023] [Indexed: 06/02/2023]
Abstract
Nanowires (NWs) offer unique opportunities for tuning the properties of III-V semiconductors by simultaneously controlling their nanoscale dimensions and switching their crystal phase between zinc-blende (ZB) and wurtzite (WZ). While much of this control has been enabled by direct, forward growth, the reverse reaction, i.e., crystal decomposition, provides very powerful means to further tailor properties towards the ultra-scaled dimensional level. Here, we use in situ transmission electron microscopy (TEM) to investigate the thermal decomposition kinetics of clean, ultrathin GaAs NWs and the role of distinctly different crystal polytypes in real-time and on the atomic scale. The whole process, from the NW growth to the decomposition, is conducted in situ without breaking vacuum to maintain pristine crystal surfaces. Radial decomposition occurs much faster for ZB- compared to WZ-phase NWs, due to the development of nano-faceted sidewall morphology and sublimation along the entire NW length. In contrast, WZ NWs form single-faceted, vertical sidewalls with decomposition proceeding only via step-flow mechanism from the NW tip. Concurrent axial decomposition is generally faster than the radial process, but is significantly faster (∼4-fold) in WZ phase, due to the absence of well-defined facets at the tip of WZ NWs. The results further show quantitatively the influence of the NW diameter on the sublimation and step-flow decomposition velocities elucidating several effects that can be exploited to fine-tune the NW dimensions.
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Affiliation(s)
- Paul Schmiedeke
- Technical University of Munich, Walter Schottky Institute, TUM School of Natural Sciences, Physics Department Garching 85747 Germany
| | - Federico Panciera
- Centre for Nanoscience and Nanotechnology, CNRS, Université Paris-Saclay 10 Boulevard Thomas Gobert 91120 Palaiseau France
| | - Jean-Christophe Harmand
- Centre for Nanoscience and Nanotechnology, CNRS, Université Paris-Saclay 10 Boulevard Thomas Gobert 91120 Palaiseau France
| | - Laurent Travers
- Centre for Nanoscience and Nanotechnology, CNRS, Université Paris-Saclay 10 Boulevard Thomas Gobert 91120 Palaiseau France
| | - Gregor Koblmüller
- Technical University of Munich, Walter Schottky Institute, TUM School of Natural Sciences, Physics Department Garching 85747 Germany
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4
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Barettin D, Shtrom IV, Reznik RR, Cirlin GE. Model of a GaAs Quantum Dot in a Direct Band Gap AlGaAs Wurtzite Nanowire. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13111737. [PMID: 37299640 DOI: 10.3390/nano13111737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 05/16/2023] [Accepted: 05/24/2023] [Indexed: 06/12/2023]
Abstract
We present a study with a numerical model based on k→·p→, including electromechanical fields, to evaluate the electromechanical and optoelectronic properties of single GaAs quantum dots embedded in direct band gap AlGaAs nanowires. The geometry and the dimensions of the quantum dots, in particular the thickness, are obtained from experimental data measured by our group. We also present a comparison between the experimental and numerically calculated spectra to support the validity of our model.
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Affiliation(s)
- Daniele Barettin
- Department of Electronic Engineering, Università Niccoló Cusano, 00133 Rome, Italy
| | - Igor V Shtrom
- Faculty of Physics, St. Petersburg State University, Universitetskaya Embankment 13B, 199034 St. Petersburg, Russia
| | - Rodion R Reznik
- Faculty of Physics, St. Petersburg State University, Universitetskaya Embankment 13B, 199034 St. Petersburg, Russia
- Department of Physics, ITMO University, Kronverkskiy pr. 49, 197101 St. Petersburg, Russia
- Department of Physics, Alferov University, Khlopina 8/3, 194021 St. Petersburg, Russia
| | - George E Cirlin
- Faculty of Physics, St. Petersburg State University, Universitetskaya Embankment 13B, 199034 St. Petersburg, Russia
- Department of Physics, ITMO University, Kronverkskiy pr. 49, 197101 St. Petersburg, Russia
- Department of Physics, Alferov University, Khlopina 8/3, 194021 St. Petersburg, Russia
- Institute for Analytical Instrumentation RAS, Rizhsky 26, 190103 St. Petersburg, Russia
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5
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Lozano MS, Gómez VJ. Epitaxial growth of crystal phase quantum dots in III-V semiconductor nanowires. NANOSCALE ADVANCES 2023; 5:1890-1909. [PMID: 36998660 PMCID: PMC10044505 DOI: 10.1039/d2na00956k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 03/06/2023] [Indexed: 06/19/2023]
Abstract
Crystal phase quantum dots (QDs) are formed during the axial growth of III-V semiconductor nanowires (NWs) by stacking different crystal phases of the same material. In III-V semiconductor NWs, both zinc blende (ZB) and wurtzite (WZ) crystal phases can coexist. The band structure difference between both crystal phases can lead to quantum confinement. Thanks to the precise control in III-V semiconductor NW growth conditions and the deep knowledge on the epitaxial growth mechanisms, it is nowadays possible to control, down to the atomic level, the switching between crystal phases in NWs forming the so-called crystal phase NW-based QDs (NWQDs). The shape and size of the NW bridge the gap between QDs and the macroscopic world. This review is focused on crystal phase NWQDs based on III-V NWs obtained by the bottom-up vapor-liquid-solid (VLS) method and their optical and electronic properties. Crystal phase switching can be achieved in the axial direction. In contrast, in the core/shell growth, the difference in surface energies between different polytypes can enable selective shell growth. One reason for the very intense research in this field is motivated by their excellent optical and electronic properties both appealing for applications in nanophotonics and quantum technologies.
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Affiliation(s)
- Miguel Sinusia Lozano
- Nanophotonics Technology Center, Universitat Politècnica de València, Camino de Vera s/n Building 8F, 2a Floor 46022 Valencia Spain
| | - Víctor J Gómez
- Nanophotonics Technology Center, Universitat Politècnica de València, Camino de Vera s/n Building 8F, 2a Floor 46022 Valencia Spain
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6
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Barettin D, Shtrom IV, Reznik RR, Mikushev SV, Cirlin GE, Auf der Maur M, Akopian N. Direct Band Gap AlGaAs Wurtzite Nanowires. NANO LETTERS 2023; 23:895-901. [PMID: 36649590 DOI: 10.1021/acs.nanolett.2c04184] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Wurtzite AlGaAs is a technologically promising yet unexplored material. Here we study it both experimentally and numerically. We develop a complete numerical model based on an 8-band k→·p→ method, including electromechanical fields, and calculate the optoelectronic properties of wurtzite AlGaAs nanowires with different Al content. We then compare them with our experimental data. Our results strongly suggest that wurtzite AlGaAs is a direct band gap material. Moreover, we have also numerically obtained the band gap of wurtzite AlAs and the valence band offset between AlAs and GaAs in the wurtzite symmetry.
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Affiliation(s)
- Daniele Barettin
- Department of Electronic Engineering, Università degli Studi Niccolò Cusano - Telematica, via don Carlo Gnocchi 3, Rome00166, Italy
| | - Igor V Shtrom
- St. Petersburg State University, Saint Petersburg199034, Russian Federation
- Alferov University, Saint Petersburg194021, Russian Federation
- Institute for Analytical Instrumentation, Russian Academy of Sciences, Saint Petersburg190103, Russian Federation
| | - Rodion R Reznik
- St. Petersburg State University, Saint Petersburg199034, Russian Federation
| | - Sergey V Mikushev
- St. Petersburg State University, Saint Petersburg199034, Russian Federation
| | - George E Cirlin
- St. Petersburg State University, Saint Petersburg199034, Russian Federation
- Alferov University, Saint Petersburg194021, Russian Federation
- Institute for Analytical Instrumentation, Russian Academy of Sciences, Saint Petersburg190103, Russian Federation
| | - Matthias Auf der Maur
- Department of Electronic Engineering, University of Rome Tor Vergata, Rome00133, Italy
| | - Nika Akopian
- DTU Department of Electrical and Photonics Engineering, Technical University of Denmark, Kgs. Lyngby2800, Denmark
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7
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Patera M, Zieliński M. Crystal field splitting and spontaneous polarization in InP crystal phase quantum dots. Sci Rep 2022; 12:15561. [PMID: 36114259 PMCID: PMC9481640 DOI: 10.1038/s41598-022-19076-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 08/24/2022] [Indexed: 11/11/2022] Open
Abstract
Crystal phase quantum dots are formed by vertically stacking zinc-blende and wurtzite phases during nanowire growth. In this work, we show, using an atomistic many-body approach, that crystal field splitting in the wurtzite phase, as well as spontaneous polarization originating from the phase interfaces, will strongly affect the properties of lowest hole states in InP crystal phase quantum dots, and in turn the excitonic optical spectra. We also show that the artifact-free modeling of crystal phase quantum dots should incorporate any additional potentials on equal footing with the electron-hole interaction. In this paper, we discuss a reliable theoretical framework that can be applied to investigate the electronic and optical properties of InP-based crystal phase quantum dots. The importance of accurate excitonic calculations for such systems is highlighted in view of their potential applications in nanowire photonics, yet further research is necessary for bringing theory and experiment in agreement.
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Affiliation(s)
- Martyna Patera
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Toruń, Poland
| | - Michał Zieliński
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Toruń, Poland.
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8
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Wu L, Wang Q, Zhuang TT, Zhang GZ, Li Y, Li HH, Fan FJ, Yu SH. A library of polytypic copper-based quaternary sulfide nanocrystals enables efficient solar-to-hydrogen conversion. Nat Commun 2022; 13:5414. [PMID: 36109517 PMCID: PMC9477825 DOI: 10.1038/s41467-022-33065-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 08/31/2022] [Indexed: 11/26/2022] Open
Abstract
Designing polytypic homojunction is an efficient way to regulate photogenerated electrons and holes, thereafter bringing desired physical and chemical properties and being attractive photocatalysts for solar-to-hydrogen conversion. However, the high-yield and controllable synthesis of well-defined polytypes especially for multinary chalcogenide - the fundamental factor favoring highly efficient solar-to-hydrogen conversion - has yet to be achieved. Here, we report a general colloidal method to construct a library of polytypic copper-based quaternary sulfide nanocrystals, including Cu2ZnSnS4, Cu2CdSnS4, Cu2CoSnS4, Cu2MnSnS4, Cu2FeSnS4, Cu3InSnS5 and Cu3GaSnS5, which can be synthesized by selective epitaxial growth of kesterite phase on wurtzite structure. Besides, this colloidal method allows the precise controlling of the homojunction number corresponding to the photocatalytic performance. The single-homojunction and double-homojunction polytypic Cu2ZnSnS4 nanocrystal photocatalysts show 2.8-fold and 3.9-fold improvement in photocatalytic hydrogen evolution rates relative to the kesterite nanocrystals, respectively. This homojunction existed in the polytypic structure opens another way to engineer photocatalysts. While polytypic semiconductors are promising for solar-to-fuel applications, preparing homojunction nanomaterials has proven challenging. Here, authors obtain a library of polytypic copper-based quaternary sulfide nanocrystals by selective epitaxial growth of kesterite phase on wurtzite structure.
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9
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Laferrière P, Yeung E, Miron I, Northeast DB, Haffouz S, Lapointe J, Korkusinski M, Poole PJ, Williams RL, Dalacu D. Unity yield of deterministically positioned quantum dot single photon sources. Sci Rep 2022; 12:6376. [PMID: 35430589 PMCID: PMC9013374 DOI: 10.1038/s41598-022-10451-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 03/23/2022] [Indexed: 11/24/2022] Open
Abstract
We report on a platform for the production of single photon devices with a fabrication yield of 100%. The sources are based on InAsP quantum dots embedded within position-controlled bottom-up InP nanowires. Using optimized growth conditions, we produce large arrays of structures having highly uniform geometries. Collection efficiencies are as high as 83% and multiphoton emission probabilities as low as 0.6% with the distribution away from optimal values associated with the excitation of other charge complexes and re-excitation processes, respectively, inherent to the above-band excitation employed. Importantly, emission peak lineshapes have Lorentzian profiles indicating that linewidths are not limited by inhomogeneous broadening but rather pure dephasing, likely elastic carrier-phonon scattering due to a high phonon occupation. This work establishes nanowire-based devices as a viable route for the scalable fabrication of efficient single photon sources and provides a valuable resource for hybrid on-chip platforms currently being developed.
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10
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Tornberg M, Sjökvist R, Kumar K, Andersen CR, Maliakkal CB, Jacobsson D, Dick KA. Direct Observations of Twin Formation Dynamics in Binary Semiconductors. ACS NANOSCIENCE AU 2022; 2:49-56. [PMID: 37101516 PMCID: PMC10125175 DOI: 10.1021/acsnanoscienceau.1c00021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
With the increased demand for controlled deterministic growth of III-V semiconductors at the nanoscale, the impact and interest of understanding defect formation and crystal structure switching becomes increasingly important. Vapor-liquid-solid (VLS) growth of semiconductor nanocrystals is an important mechanism for controlling and studying the formation of individual crystal layers and stacking defects. Using in situ studies, combining atomic resolution of transmission electron microscopy and controlled VLS crystal growth using metal organic chemical vapor deposition, we investigate the simplest achievable change in atomic layer stacking-single twinned layers formed in GaAs. Using Au-assisted GaAs nanowires of various diameters, we study the formation of individual layers with atomic resolution to reveal the growth difference in forming a twin defect. We determine that the formation of a twinned layer occurs significantly more slowly than that of a normal crystal layer. To understand this, we conduct thermodynamic modeling and determine that the propagation of a twin is limited by the energy cost of forming the twin interface. Finally, we determine that the slower propagation of twinned layers increases the probability of additional layers nucleating, such that multiple layers grow simultaneously. This observation challenges the current understanding that continuous uniform epitaxial growth, especially in the case of liquid-metal assisted nanowires, proceeds one single layer at a time and that its progression is limited by the nucleation rate.
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Affiliation(s)
- Marcus Tornberg
- Centre
for Analysis and Synthesis, Lund University, Box 118, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
| | - Robin Sjökvist
- Centre
for Analysis and Synthesis, Lund University, Box 118, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
| | - Krishna Kumar
- Centre
for Analysis and Synthesis, Lund University, Box 118, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
| | - Christopher R. Andersen
- Centre
for Analysis and Synthesis, Lund University, Box 118, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
- National
Centre for Nano Fabrication and Characterization, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Carina B. Maliakkal
- Centre
for Analysis and Synthesis, Lund University, Box 118, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
| | - Daniel Jacobsson
- Centre
for Analysis and Synthesis, Lund University, Box 118, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
- National
Center for High Resolution Electron Microscopy (nCHREM), Lund University, 22100 Lund, Sweden
| | - Kimberly A. Dick
- Centre
for Analysis and Synthesis, Lund University, Box 118, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
- National
Center for High Resolution Electron Microscopy (nCHREM), Lund University, 22100 Lund, Sweden
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11
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Lee JH, Jeon WB, Moon JS, Lee J, Han SW, Bodrog Z, Gali A, Lee SY, Kim JH. Strong Zero-Phonon Transition from Point Defect-Stacking Fault Complexes in Silicon Carbide Nanowires. NANO LETTERS 2021; 21:9187-9194. [PMID: 34677068 DOI: 10.1021/acs.nanolett.1c03013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Crystallographic defects such as vacancies and stacking faults engineer electronic band structure at the atomic level and create zero- and two-dimensional quantum structures in crystals. The combination of these point and planar defects can generate a new type of defect complex system. Here, we investigate silicon carbide nanowires that host point defects near stacking faults. These point-planar defect complexes in the nanowire exhibit outstanding optical properties of high-brightness single photons (>360 kcounts/s), a fast recombination time (<1 ns), and a high Debye-Waller factor (>50%). These distinct optical properties of coupled point-planar defects lead to an unusually strong zero-phonon transition, essential for achieving highly efficient quantum interactions between multiple qubits. Our findings can be extended to other defects in various materials and therefore offer a new perspective for engineering defect qubits.
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Affiliation(s)
- Jin Hee Lee
- Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Woong Bae Jeon
- Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Jong Sung Moon
- Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Junghyun Lee
- Center for Quantum Information, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Sang-Wook Han
- Center for Quantum Information, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Zoltán Bodrog
- Wigner Research Centre for Physics, P.O. Box 49, H-1525 Budapest, Hungary
| | - Adam Gali
- Wigner Research Centre for Physics, P.O. Box 49, H-1525 Budapest, Hungary
- Department of Atomic Physics, Budapest University of Technology and Economics, Budafoki út 8., H-1111 Budapest, Hungary
| | - Sang-Yun Lee
- Center for Quantum Information, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
- Department of Physics and Photon Science, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea
| | - Je-Hyung Kim
- Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
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12
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Sonner MM, Gnedel M, Berlin JC, Rudolph D, Koblmüller G, Krenner HJ. Sub-nanosecond acousto-electric carrier redistribution dynamics and transport in polytypic GaAs nanowires. NANOTECHNOLOGY 2021; 32:505209. [PMID: 34584026 DOI: 10.1088/1361-6528/ac2ac2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 09/27/2021] [Indexed: 06/13/2023]
Abstract
The authors report on a combined structural, optical and acousto-electric study of polytypic GaAs nanowires. Two types of nanowires with different zincblende and wurtzite crystal phase mixing are identified by transmission electron microscopy and photoluminescence spectroscopy. The nanowires exhibit characteristic recombination channels which are assigned to different types of spatially direct recombination (electron and hole within the same crystal phase segment) and spatially indirect recombination (electron and holes localized in different segments). Contact-free acousto-optoelectric spectroscopy is employed to resolve spatiotemporal charge carrier dynamics between different recombination channels induced by a piezoelectric surface acoustic wave. The observed suppression of the emission and its dynamic temporal modulation shows unambiguous fingerprints of the local bandedge variations induced by the crystal phase mixing. A nanowire, which exhibits a variation from a near-pristine zinc blende crystal structure to a highly mixed crystal phase, shows a clear dependence on the propagation direction of the acoustic wave. In contrast, no pronounced directionality is found for a nanowire with an extended near-pristine zincblende segment. The experimental findings are corroborated by solving the drift and diffusion equations of electrons and holes induced by the surface acoustic wave. The key characteristics observed in our experimental data are well reproduced in the numerical simulations by assuming two general bandedge modulations and realistic parameters for the bandedge discontinuities and transport mobilities of electrons and holes. This evidences that even all relevant physical processes are accounted for in the model.
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Affiliation(s)
- Maximilian M Sonner
- Lehrstuhl für Experimentalphysik 1, Institut für Physik, Universität Augsburg, Universitätsstraße 1, D-86159 Augsburg, Germany
| | - Maximilian Gnedel
- Lehrstuhl für Experimentalphysik 1, Institut für Physik, Universität Augsburg, Universitätsstraße 1, D-86159 Augsburg, Germany
| | - Johannes C Berlin
- Lehrstuhl für Experimentalphysik 1, Institut für Physik, Universität Augsburg, Universitätsstraße 1, D-86159 Augsburg, Germany
| | - Daniel Rudolph
- Walter Schottky Institut and Physik Department, Technische Universität München, Am Coulombwall 4, D-85748 Garching, Germany
| | - Gregor Koblmüller
- Walter Schottky Institut and Physik Department, Technische Universität München, Am Coulombwall 4, D-85748 Garching, Germany
| | - Hubert J Krenner
- Lehrstuhl für Experimentalphysik 1, Institut für Physik, Universität Augsburg, Universitätsstraße 1, D-86159 Augsburg, Germany
- Physikalisches Institut, Universität Münster, Wilhelm-Klemm-Str. 10, D-48149 Münster, Germany
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13
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Zhang Y, Velichko AV, Fonseka HA, Parkinson P, Gott JA, Davis G, Aagesen M, Sanchez AM, Mowbray D, Liu H. Defect-Free Axially Stacked GaAs/GaAsP Nanowire Quantum Dots with Strong Carrier Confinement. NANO LETTERS 2021; 21:5722-5729. [PMID: 34181433 PMCID: PMC8289304 DOI: 10.1021/acs.nanolett.1c01461] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 06/25/2021] [Indexed: 06/13/2023]
Abstract
Axially stacked quantum dots (QDs) in nanowires (NWs) have important applications in nanoscale quantum devices and lasers. However, there is lack of study of defect-free growth and structure optimization using the Au-free growth mode. We report a detailed study of self-catalyzed GaAsP NWs containing defect-free axial GaAs QDs (NWQDs). Sharp interfaces (1.8-3.6 nm) allow closely stack QDs with very similar structural properties. High structural quality is maintained when up to 50 GaAs QDs are placed in a single NW. The QDs maintain an emission line width of <10 meV at 140 K (comparable to the best III-V QDs, including nitrides) after having been stored in an ambient atmosphere for over 6 months and exhibit deep carrier confinement (∼90 meV) and the largest reported exciton-biexciton splitting (∼11 meV) for non-nitride III-V NWQDs. Our study provides a solid foundation to build high-performance axially stacked NWQD devices that are compatible with CMOS technologies.
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Affiliation(s)
- Yunyan Zhang
- Department
of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
- Department
of Physics, Universität Paderborn, Warburger Straße 100, 33098 Paderborn, Germany
| | - Anton V. Velichko
- Department
of Physics and Astronomy, University of
Sheffield, Sheffield S3 7RH, United Kingdom
| | - H. Aruni Fonseka
- Department
of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Patrick Parkinson
- School
Department of Physics and Astronomy and the Photon Science Institute, University of Manchester, Manchester M13 9PL, United Kingdom
| | - James A. Gott
- 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
| | - Martin Aagesen
- Center for
Quantum Devices, Niels Bohr Institute, University
of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Ana M. Sanchez
- Department
of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - David Mowbray
- Department
of Physics and Astronomy, University of
Sheffield, Sheffield S3 7RH, United Kingdom
| | - Huiyun Liu
- Department
of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
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14
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Wang N, Wong WW, Yuan X, Li L, Jagadish C, Tan HH. Understanding Shape Evolution and Phase Transition in InP Nanostructures Grown by Selective Area Epitaxy. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2100263. [PMID: 33856732 DOI: 10.1002/smll.202100263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 03/08/2021] [Indexed: 06/12/2023]
Abstract
There is a strong demand for III-V nanostructures of different geometries and in the form of interconnected networks for quantum science applications. This can be achieved by selective area epitaxy (SAE) but the understanding of crystal growth in these complicated geometries is still insufficient to engineer the desired shape. Here, the shape evolution and crystal structure of InP nanostructures grown by SAE on InP substrates of different orientations are investigated and a unified understanding to explain these observations is established. A strong correlation between growth direction and crystal phase is revealed. Wurtzite (WZ) and zinc-blende (ZB) phases form along <111>A and <111>B directions, respectively, while crystal phase remains the same along other low-index directions. The polarity induced crystal structure difference is explained by thermodynamic difference between the WZ and ZB phase nuclei on different planes. Growth from the openings is essentially determined by pattern confinement and minimization of the total surface energy, regardless of substrate orientations. A novel type-II WZ/ZB nanomembrane homojunction array is obtained by tailoring growth directions through alignment of the openings along certain crystallographic orientations. The understanding in this work lays the foundation for the design and fabrication of advanced III-V semiconductor devices based on complex geometrical nanostructures.
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Affiliation(s)
- Naiyin Wang
- Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, ACT 2601, Australia
| | - Wei Wen Wong
- Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, ACT 2601, Australia
| | - Xiaoming Yuan
- Hunan Key Laboratory of Super Microstructure and Ultrafast Process, School of Physics and Electronics, Central South University, Changsha, Hunan, 410083, P. R. China
| | - Li Li
- Australian National Fabrication Facility ACT Node, Research School of Physics, The Australian National University, Canberra, ACT 2601, Australia
| | - Chennupati Jagadish
- Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, ACT 2601, Australia
- ARC Centre of Excellence for Transformative Meta-Optical System, Research School of Physics, The Australian National University, Canberra, ACT 2601, Australia
| | - Hark Hoe Tan
- Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, ACT 2601, Australia
- ARC Centre of Excellence for Transformative Meta-Optical System, Research School of Physics, The Australian National University, Canberra, ACT 2601, Australia
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15
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Seidl J, Gluschke JG, Yuan X, Tan HH, Jagadish C, Caroff P, Micolich AP. Postgrowth Shaping and Transport Anisotropy in Two-Dimensional InAs Nanofins. ACS NANO 2021; 15:7226-7236. [PMID: 33825436 DOI: 10.1021/acsnano.1c00483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We report on the postgrowth shaping of free-standing two-dimensional (2D) InAs nanofins that are grown by selective-area epitaxy and mechanically transferred to a separate substrate for device fabrication. We use a citric acid-based wet etch that enables complex shapes, for example, van der Pauw cloverleaf structures, with patterning resolution down to 150 nm as well as partial thinning of the nanofin to improve local gate response. We exploit the high sensitivity of the cloverleaf structures to transport anisotropy to address the fundamental question of whether there is a measurable transport anisotropy arising from wurtzite/zincblende polytypism in 2D InAs nanostructures. We demonstrate a mobility anisotropy of order 2-4 at room temperature arising from polytypic stacking faults in our nanofins. Our work highlights a key materials consideration for devices featuring self-assembled 2D III-V nanostructures using advanced epitaxy methods.
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Affiliation(s)
- Jakob Seidl
- School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Jan G Gluschke
- School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Xiaoming Yuan
- ARC Centre of Excellence for Transformative Meta-Optical Systems, Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - H Hoe Tan
- ARC Centre of Excellence for Transformative Meta-Optical Systems, Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Chennupati Jagadish
- ARC Centre of Excellence for Transformative Meta-Optical Systems, Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Philippe Caroff
- ARC Centre of Excellence for Transformative Meta-Optical Systems, Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Adam P Micolich
- School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
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16
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Koval OY, Fedorov VV, Bolshakov AD, Eliseev IE, Fedina SV, Sapunov GA, Udovenko SA, Dvoretckaia LN, Kirilenko DA, Burkovsky RG, Mukhin IS. XRD Evaluation of Wurtzite Phase in MBE Grown Self-Catalyzed GaP Nanowires. NANOMATERIALS 2021; 11:nano11040960. [PMID: 33918690 PMCID: PMC8070561 DOI: 10.3390/nano11040960] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 03/29/2021] [Accepted: 04/06/2021] [Indexed: 01/11/2023]
Abstract
Control and analysis of the crystal phase in semiconductor nanowires are of high importance due to the new possibilities for strain and band gap engineering for advanced nanoelectronic and nanophotonic devices. In this letter, we report the growth of the self-catalyzed GaP nanowires with a high concentration of wurtzite phase by molecular beam epitaxy on Si (111) and investigate their crystallinity. Varying the growth temperature and V/III flux ratio, we obtained wurtzite polytype segments with thicknesses in the range from several tens to 500 nm, which demonstrates the high potential of the phase bandgap engineering with highly crystalline self-catalyzed phosphide nanowires. The formation of rotational twins and wurtzite polymorph in vertical nanowires was observed through complex approach based on transmission electron microscopy, powder X-ray diffraction, and reciprocal space mapping. The phase composition, volume fraction of the crystalline phases, and wurtzite GaP lattice parameters were analyzed for the nanowires detached from the substrate. It is shown that the wurtzite phase formation occurs only in the vertically-oriented nanowires during vapor-liquid-solid growth, while the wurtzite phase is absent in GaP islands parasitically grown via the vapor-solid mechanism. The proposed approach can be used for the quantitative evaluation of the mean volume fraction of polytypic phase segments in heterostructured nanowires that are highly desirable for the optimization of growth technologies.
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Affiliation(s)
- Olga Yu. Koval
- Nanotechnology Research and Education Centre of the Russian Academy of Sciences, Alferov University, Khlopina 8/3, 194021 Saint Petersburg, Russia; (V.V.F.); (A.D.B.); (I.E.E.); (S.V.F.); (G.A.S.); (L.N.D.); (I.S.M.)
- Correspondence:
| | - Vladimir V. Fedorov
- Nanotechnology Research and Education Centre of the Russian Academy of Sciences, Alferov University, Khlopina 8/3, 194021 Saint Petersburg, Russia; (V.V.F.); (A.D.B.); (I.E.E.); (S.V.F.); (G.A.S.); (L.N.D.); (I.S.M.)
- Institute of Physics, Nanotechnology and Telecommunications, Peter the Great Saint Petersburg Polytechnic University, Politekhnicheskaya 29, 195251 Saint Petersburg, Russia; (S.A.U.); (R.G.B.)
| | - Alexey D. Bolshakov
- Nanotechnology Research and Education Centre of the Russian Academy of Sciences, Alferov University, Khlopina 8/3, 194021 Saint Petersburg, Russia; (V.V.F.); (A.D.B.); (I.E.E.); (S.V.F.); (G.A.S.); (L.N.D.); (I.S.M.)
- School of Photonics, ITMO University, Kronverksky Prospekt 49, 197101 Saint Petersburg, Russia
| | - Igor E. Eliseev
- Nanotechnology Research and Education Centre of the Russian Academy of Sciences, Alferov University, Khlopina 8/3, 194021 Saint Petersburg, Russia; (V.V.F.); (A.D.B.); (I.E.E.); (S.V.F.); (G.A.S.); (L.N.D.); (I.S.M.)
| | - Sergey V. Fedina
- Nanotechnology Research and Education Centre of the Russian Academy of Sciences, Alferov University, Khlopina 8/3, 194021 Saint Petersburg, Russia; (V.V.F.); (A.D.B.); (I.E.E.); (S.V.F.); (G.A.S.); (L.N.D.); (I.S.M.)
| | - Georgiy A. Sapunov
- Nanotechnology Research and Education Centre of the Russian Academy of Sciences, Alferov University, Khlopina 8/3, 194021 Saint Petersburg, Russia; (V.V.F.); (A.D.B.); (I.E.E.); (S.V.F.); (G.A.S.); (L.N.D.); (I.S.M.)
| | - Stanislav A. Udovenko
- Institute of Physics, Nanotechnology and Telecommunications, Peter the Great Saint Petersburg Polytechnic University, Politekhnicheskaya 29, 195251 Saint Petersburg, Russia; (S.A.U.); (R.G.B.)
| | - Liliia N. Dvoretckaia
- Nanotechnology Research and Education Centre of the Russian Academy of Sciences, Alferov University, Khlopina 8/3, 194021 Saint Petersburg, Russia; (V.V.F.); (A.D.B.); (I.E.E.); (S.V.F.); (G.A.S.); (L.N.D.); (I.S.M.)
| | - Demid A. Kirilenko
- Ioffe Institute, Politekhnicheskaya 26, 194021 Saint Petersburg, Russia;
| | - Roman G. Burkovsky
- Institute of Physics, Nanotechnology and Telecommunications, Peter the Great Saint Petersburg Polytechnic University, Politekhnicheskaya 29, 195251 Saint Petersburg, Russia; (S.A.U.); (R.G.B.)
| | - Ivan S. Mukhin
- Nanotechnology Research and Education Centre of the Russian Academy of Sciences, Alferov University, Khlopina 8/3, 194021 Saint Petersburg, Russia; (V.V.F.); (A.D.B.); (I.E.E.); (S.V.F.); (G.A.S.); (L.N.D.); (I.S.M.)
- School of Photonics, ITMO University, Kronverksky Prospekt 49, 197101 Saint Petersburg, Russia
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17
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Xue M, Li M, Huang Y, Chen R, Li Y, Wang J, Xing Y, Chen J, Yan H, Xu H, Chen J. Observation and Ultrafast Dynamics of Inter-Sub-Band Transition in InAs Twinning Superlattice Nanowires. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2004120. [PMID: 32876964 DOI: 10.1002/adma.202004120] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/28/2020] [Indexed: 06/11/2023]
Abstract
A variety of infrared applications rely on semiconductor superlattices, including, notably, the realization of high-power, compact quantum cascade lasers. Requirements for atomically smooth interface and limited lattice matching options set high technical standards for fabricating applicable heterostructure devices. The semiconductor twinning superlattice (TSL) forms in a single compound with periodically spaced twin boundaries and sharp interface junctions and can be grown with convenient synthesis methods. Therefore, employing semiconductor TSL may facilitate the development of optoelectronic applications related to superlattice structures. Here, it is shown that InAs TSL nanowires generate inter-sub-band transition channels due to the band projection and the Bragg-like electron reflection. The findings reveal the physical mechanisms of inter-sub-band transitions in TSL structure and suggest that TSL structures are promising candidates for mid-infrared optoelectronic applications.
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Affiliation(s)
- Mengfei Xue
- Institute of Physics, Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics, P.O. Box 603, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ming Li
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing, 100871, China
| | - Yisheng Huang
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing, 100871, China
| | - Runkun Chen
- Institute of Physics, Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics, P.O. Box 603, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yunliang Li
- Institute of Physics, Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics, P.O. Box 603, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jingyun Wang
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing, 100871, China
| | - Yingjie Xing
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing, 100871, China
| | - Jianjun Chen
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Collaborative Innovation Center of Quantum Matter, Peking University, Beijing, 100871, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China
| | - Hugen Yan
- State Key Laboratory of Surface Physics and Department of Physics and Key Laboratory of Micro and Nano-Photonic Structures (Ministry of Education), Fudan University, Shanghai, 200433, China
| | - Hongqi Xu
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing, 100871, China
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China
| | - Jianing Chen
- Institute of Physics, Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics, P.O. Box 603, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
- Songshan Lake Materials Laboratory, Dongguan, 523808, China
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18
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Akamatsu T, Tomioka K, Motohisa J. Demonstration of InP/InAsP/InP axial heterostructure nanowire array vertical LEDs. NANOTECHNOLOGY 2020; 31:394003. [PMID: 32658871 DOI: 10.1088/1361-6528/ab9bd2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Semiconductor nanowires (NWs), which have nanoscale footprints, enable us to realize various quantum structures with excellent position and size controllability, utilizing a wide range of materials for heterostructures. In addition, enhancing light extraction and controlling spontaneous emission by modifying their size and shape are possible. Thus, NWs are promising materials for nanoscale light sources applicable from visible to telecommunication bands. In this study, we grew InP/InAsP/InP axial heterostructure NWs, where the InAsP layer was embedded to serve as an active layer, by selective-area growth and demonstrated vertical NW array light-emitting diodes (LEDs) as a step towards realizing on-demand single photon sources. The NW array LEDs showed rectifying characteristics and electroluminescence originating from the embedded InAsP layer in the near-infrared region.
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Affiliation(s)
- Tomoya Akamatsu
- Graduate School of Information Science and Technology and Research Center for Integrated Quantum Electronics, Hokkaido University, North 14 West 9, Sapporo 060-0814, Japan
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19
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All-optical charging and charge transport in quantum dots. Sci Rep 2020; 10:14911. [PMID: 32913255 PMCID: PMC7483522 DOI: 10.1038/s41598-020-71601-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 08/14/2020] [Indexed: 11/26/2022] Open
Abstract
Optically active quantum dots are one of the promising candidates for fundamental building blocks in quantum technology. Many practical applications would comprise of multiple coupled quantum dots, each of which must be individually chargeable. However, the most advanced demonstrations are limited to devices with only a single dot, and individual charging has neither been demonstrated nor proposed for an array of optically active quantum dots. Here we propose and numerically demonstrate a method for controlled charging of multiple quantum dots and charge transport between the dots. We show that our method can be implemented in realistic structures with fidelities greater than 99.9%. The scheme is based on all-optical resonant manipulation of charges in an array of quantum dots formed by a type-II band alignment, such as crystal-phase quantum dots in nanowires. Our work opens new practical avenues for realizations of advanced quantum photonic devices, for instance, solid-state quantum registers with a photonic interface.
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20
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Jaffal A, Regreny P, Patriarche G, Chauvin N, Gendry M. Density-controlled growth of vertical InP nanowires on Si(111) substrates. NANOTECHNOLOGY 2020; 31:354003. [PMID: 32428880 DOI: 10.1088/1361-6528/ab9475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
A procedure to achieve the density-controlled growth of gold-catalyzed InP nanowires (NWs) on (111) silicon substrates using the vapor-liquid-solid method by molecular beam epitaxy is reported. We develop an effective and mask-free method based on controlling the number and the size of the Au-In catalyst droplets in addition to the conditions for the NW nucleation. We show that the NW density can be tuned with values in the range of 18 µm-2 to <0.1 µm-2 by the suitable choice of the In/Au catalyst beam equivalent pressure (BEP) ratio, by the phosphorous BEP and the growth temperature. The same degree of control is transferred to InAs/InP quantum dot-nanowires, taking advantage of the ultra-low density to study by micro-photoluminescence the optical properties of a single quantum dot-nanowires emitting in the telecom band monolithically grown on silicon. Optical spectroscopy at cryogenic temperature successfully confirmed the relevance of our method to excite single InAs quantum dots on the as-grown sample, which opens the path for large-scale applications based on single quantum dot-nanowire devices integrated on silicon. .
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Affiliation(s)
- A Jaffal
- Institut des Nanotechnologies des Lyon-INL, UMR 5270 CNRS, INSA de Lyon, Université de Lyon, 7 avenue Jean Capelle, 69621, Villeurbanne cedex, France. Institut des Nanotechnologies des Lyon-INL, UMR 5270 CNRS, Ecole Centrale de Lyon, Université de Lyon, 36 avenue Guy de Collongue, 69134, Ecully cedex, France
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21
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Yuan X, Liu K, Skalsky S, Parkinson P, Fang L, He J, Tan HH, Jagadish C. Carrier dynamics and recombination mechanisms in InP twinning superlattice nanowires. OPTICS EXPRESS 2020; 28:16795-16804. [PMID: 32549494 DOI: 10.1364/oe.388518] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 05/13/2020] [Indexed: 06/11/2023]
Abstract
Nominal dopant-free zinc blende twinning superlattice InP nanowires have been grown with high crystal-quality and taper-free morphology. Here, we demonstrate its superior optical performance and clarify the different carrier recombination mechanisms at different temperatures using a time resolved photoluminescence study. The existence of regular twin planes and lateral overgrowth do not significantly increase the defect density. At room temperature, the as-grown InP nanowires have a strong emission at 1.348 eV and long minority carrier lifetime (∼3 ns). The carrier recombination dynamics is mainly dominated by nonradiative recombination due to surface trapping states; a wet chemical etch to reduce the surface trapping density thus boosts the emission intensity and increases the carrier lifetime to 7.1 ns. This nonradiative recombination mechanism dominates for temperatures above 155 K, and the carrier lifetime decreases with increasing temperature. However, radiative recombination dominates the carrier dynamics at temperature below ∼75 K, and a strong donor-bound exciton emission with a narrow emission linewidth of 4.5 meV is observed. Consequently, carrier lifetime increases with temperature. By revealing carrier recombination mechanisms over the temperature range 10-300 K, we demonstrate the attraction of using InP nanostructure for photonics and optoelectronic applications.
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22
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Płachta J, Kaleta A, Kret S, Kazimierczuk T, Połczyńska K, Kossacki P, Karczewski G, Wojtowicz T, Kossut J, Wojnar P. Polarization and magneto-optical properties of excitonic emission from wurtzite CdTe/(Cd,Mg)Te core/shell nanowires. NANOTECHNOLOGY 2020; 31:215710. [PMID: 32050170 DOI: 10.1088/1361-6528/ab7589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Wurtzite CdTe and (Cd,Mn)Te nanowires embedded in (Cd,Mg)Te shells are grown by employing vapour-liquid-solid growth mechanism in a system for molecular beam epitaxy. A combined study involving cathodoluminescence, transmission electron microscopy and micro-photoluminescence is used to correlate optical and structural properties in these structures. Typical features of excitonic emission from individual wurtzite nanowires are highlighted including the emission energy of 1.65 eV, polarization properties and the appearance B-exciton related emission at high excitation densities. Angle dependent magneto-optical study performed on individual (Cd,Mn)Te nanowires reveals heavy-hole-like character of A-excitons typical for wurtzite structure and allows to determine the crystal field splitting, ΔCR. The impact of the strain originating from the lattice mismatched shell is discussed and supported by theoretical calculations.
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Affiliation(s)
- Jakub Płachta
- Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, PL-02-668 Warsaw, Poland
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23
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Maliakkal CB, Mårtensson EK, Tornberg MU, Jacobsson D, Persson AR, Johansson J, Wallenberg LR, Dick KA. Independent Control of Nucleation and Layer Growth in Nanowires. ACS NANO 2020; 14:3868-3875. [PMID: 32049491 PMCID: PMC7307954 DOI: 10.1021/acsnano.9b09816] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 02/12/2020] [Indexed: 05/10/2023]
Abstract
Control of the crystallization process is central to developing nanomaterials with atomic precision to meet the demands of electronic and quantum technology applications. Semiconductor nanowires grown by the vapor-liquid-solid process are a promising material system in which the ability to form components with structure and composition not achievable in bulk is well-established. Here, we use in situ TEM imaging of Au-catalyzed GaAs nanowire growth to understand the processes by which the growth dynamics are connected to the experimental parameters. We find that two sequential steps in the crystallization process-nucleation and layer growth-can occur on similar time scales and can be controlled independently using different growth parameters. Importantly, the layer growth process contributes significantly to the growth time for all conditions and will play a major role in determining material properties such as compositional uniformity, dopant density, and impurity incorporation. The results are understood through theoretical simulations correlating the growth dynamics, liquid droplet, and experimental parameters. The key insights discussed here are not restricted to Au-catalyzed GaAs nanowire growth but can be extended to most compound nanowire growths in which the different growth species has very different solubility in the catalyst particle.
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Affiliation(s)
- Carina B. Maliakkal
- Centre
for Analysis and Synthesis, Lund University, Box 124, 22100 Lund, Sweden
- Solid
State Physics, Lund University, Box 118, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
| | - Erik K. Mårtensson
- Solid
State Physics, Lund University, Box 118, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
| | - Marcus Ulf Tornberg
- Solid
State Physics, Lund University, Box 118, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
| | - Daniel Jacobsson
- Centre
for Analysis and Synthesis, Lund University, Box 124, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
- National
Center for High Resolution Electron Microscopy, Lund University, Box 124, 22100 Lund, Sweden
| | - Axel R. Persson
- Centre
for Analysis and Synthesis, Lund University, Box 124, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
- National
Center for High Resolution Electron Microscopy, Lund University, Box 124, 22100 Lund, Sweden
| | - Jonas Johansson
- Solid
State Physics, Lund University, Box 118, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
| | - Lars Reine Wallenberg
- Centre
for Analysis and Synthesis, Lund University, Box 124, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
- National
Center for High Resolution Electron Microscopy, Lund University, Box 124, 22100 Lund, Sweden
| | - Kimberly A. Dick
- Centre
for Analysis and Synthesis, Lund University, Box 124, 22100 Lund, Sweden
- Solid
State Physics, Lund University, Box 118, 22100 Lund, Sweden
- NanoLund, Lund University, 22100 Lund, Sweden
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24
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Vainorius N, Lehmann S, Dick KA, Pistol ME. Non-resonant Raman scattering of wurtzite GaAs and InP nanowires. OPTICS EXPRESS 2020; 28:11016-11022. [PMID: 32403621 DOI: 10.1364/oe.386597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 03/18/2020] [Indexed: 06/11/2023]
Abstract
It is now possible to synthesize the wurtzite crystal phase of most III-V semiconductors in the form of nanowires. This sparks interest for fundamental research and adds extra degrees of freedom for designing novel devices. However, the understanding of many properties, such as phonon dispersion, of these wurtzite semiconductors is not yet complete, despite the extensive number of studies published. The E2L and E2H phonon modes exist in the wurtzite crystal phase only (not in zinc blende) where the E2H mode has been already experimentally observed in Ga and In arsenides and phosphides, while the E2L mode has been observed in GaP, but not in GaAs or InP. In order to determine the energy of E2L in wurtzite GaAs and InP, we performed Raman scattering measurements on wurtzite GaAs and InP nanowires. We found clear evidence of the E2L phonon mode at 64 cm-1 and 54 cm-1, respectively. Polarization-dependent experiments revealed similar selection rules for both the E2L and the E2H phonon modes (as expected) where the intensity peaked with excitation and detection polarization being perpendicular to the [0001] crystallographic direction. We further find that the splitting between the E1(TO) and A1(TO) modes is around 2 cm-1 in wurtzite GaAs and below 1 cm-1 in wurtzite InP. We believe these results will be useful for a better understanding of phonons in wurtzite crystal phase of III-V semiconductors as well as for testing and improving phonon dispersion calculations.
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25
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Panciera F, Baraissov Z, Patriarche G, Dubrovskii VG, Glas F, Travers L, Mirsaidov U, Harmand JC. Phase Selection in Self-catalyzed GaAs Nanowires. NANO LETTERS 2020; 20:1669-1675. [PMID: 32027145 DOI: 10.1021/acs.nanolett.9b04808] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Crystal phase switching between the zincblende and wurtzite structures in III-V nanowires is crucial from the fundamental viewpoint as well as for electronic and photonic applications of crystal phase heterostructures. Here, the results of in situ monitoring of self-catalyzed vapor-liquid-solid growth of GaAs nanowires by molecular beam epitaxy inside a transmission electron microscope are presented. It is demonstrated that the occurrence of the zincblende or wurtzite phase in self-catalyzed nanowires is determined by the sole parameter, the droplet contact angle, which can be finely tuned by changing the group III and V fluxes. The zincblende phase forms at small (<100°) and large (>125°) contact angles, whereas pure wurtzite phase is observed for intermediate contact angles. Wurtzite nanowires are restricted by vertical sidewalls, whereas zincblende nanowires taper or develop the truncated edge at their top. These findings are explained within a dedicated model for the surface energetics. These results give a clear route for the crystal phase control in Au-free III-V nanowires. On a more general note, in situ growth monitoring with atomic resolution and at the technological-relevant growth rates is shown to be a powerful tool for the fine-tuning of material properties at the nanoscale.
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Affiliation(s)
- Federico Panciera
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France
- Centre for BioImaging Sciences, Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117557, Singapore
| | - Zhaslan Baraissov
- Centre for BioImaging Sciences, Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117557, Singapore
- Centre for Advanced 2D Materials and Department of Physics, National University of Singapore, Science Drive 4, 117543, Singapore
| | - Gilles Patriarche
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France
| | | | - Frank Glas
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France
| | - Laurent Travers
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France
| | - Utkur Mirsaidov
- Centre for BioImaging Sciences, Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117557, Singapore
- Centre for Advanced 2D Materials and Department of Physics, National University of Singapore, Science Drive 4, 117543, Singapore
| | - Jean-Christophe Harmand
- Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France
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26
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Abstract
Semiconducting nanowires, unlike bulk, can be grown in both wurtzite and zincblende crystal phases. This unique feature allows for growth and investigation of technologically important and previously unexplored materials, such as wurtzite AlGaAs. Here we grow a series of wurtzite AlGaAs nanowires with Al content varying from 0.1 to 0.6, on silicon substrates and through a comparative structural and optical analysis we experimentally derive, for the first time, the formula for the bandgap of wurtzite AlGaAs. Moreover, bright emission and short lifetime of our nanowires suggest that wurtzite AlGaAs is a direct bandgap material.
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Jaffal A, Redjem W, Regreny P, Nguyen HS, Cueff S, Letartre X, Patriarche G, Rousseau E, Cassabois G, Gendry M, Chauvin N. InAs quantum dot in a needlelike tapered InP nanowire: a telecom band single photon source monolithically grown on silicon. NANOSCALE 2019; 11:21847-21855. [PMID: 31696191 DOI: 10.1039/c9nr06114b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Realizing single photon sources emitting in the telecom band on silicon substrates is essential to reach complementary-metal-oxide-semiconductor (CMOS) compatible devices that secure communications over long distances. In this work, we propose the monolithic growth of needlelike tapered InAs/InP quantum dot-nanowires (QD-NWs) on silicon substrates with a small taper angle and a nanowire diameter tailored to support a single mode waveguide. Such a NW geometry is obtained by a controlled balance over axial and radial growths during the gold-catalyzed growth of the NWs by molecular beam epitaxy. This allows us to investigate the impact of the taper angle on the emission properties of a single InAs/InP QD-NW. At room temperature, a Gaussian far-field emission profile in the telecom O-band with a beam divergence angle θ = 30° is demonstrated using a single InAs QD embedded in a 2° tapered InP NW. Moreover, single photon emission is observed at cryogenic temperature for an off-resonant excitation and the best result, g2(0) = 0.05, is obtained for a 7° tapered NW. This all-encompassing study paves the way for the monolithic growth on silicon of an efficient single photon source in the telecom band based on InAs/InP QD-NWs.
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Affiliation(s)
- Ali Jaffal
- Université de Lyon, Institut des Nanotechnologies de Lyon, UMR 5270 CNRS, INSA de Lyon, 7 avenue Jean Capelle, 69621 Villeurbanne cedex, France.
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28
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Jansson M, Francaviglia L, La R, Balagula R, Stehr JE, Tu CW, Fontcuberta I Morral A, Chen WM, Buyanova IA. Increasing N content in GaNAsP nanowires suppresses the impact of polytypism on luminescence. NANOTECHNOLOGY 2019; 30:405703. [PMID: 31242464 DOI: 10.1088/1361-6528/ab2cdb] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Cathodoluminescence (CL) and micro-photoluminescence spectroscopies are employed to investigate effects of structural defects on carrier recombination in GaNAsP nanowires (NWs) grown by molecular beam epitaxy on Si substrates. In the NWs with a low N content of 0.08%, these defects are found to promote non-radiative (NR) recombination, which causes spatial variation of the CL peak position and its intensity. Unexpectedly, these detrimental effects can be suppressed even by a small increase in the nitrogen composition from 0.08% to 0.12%. This is attributed to more efficient trapping of excited carriers/excitons to the localized states promoted by N-induced localization and also the presence of other NR channels. At room temperature, the structural defects no longer dominate in carrier recombination even in the NWs with the lower nitrogen content, likely due to increasing importance of other recombination channels. Our work underlines the need in eliminating important thermally activated NR defects, other than the structural defects, for future optoelectronic applications of these NWs.
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Affiliation(s)
- Mattias Jansson
- Department of Physics, Chemistry and Biology, Linköping University, SE-58183 Linköping, Sweden
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29
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Buyanova IA, Chen WM. Dilute nitrides-based nanowires-a promising platform for nanoscale photonics and energy technology. NANOTECHNOLOGY 2019; 30:292002. [PMID: 30933933 DOI: 10.1088/1361-6528/ab1516] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Dilute nitrides are novel III-V-N semiconductor alloys promising for a great variety of applications ranging from nanoscale light emitters and solar cells to energy production via photoelectrochemical reactions and to nano-spintronics. These alloys have become available in the one-dimensional geometry only most recently, thanks to the advances in the nanowire (NW) growth utilizing molecular beam epitaxy. In this review we will summarize growth approaches currently utilized for the fabrication of such novel dilute nitride-based NWs, discuss their structural, defect-related and optical properties, as well as provide several examples of their potential applications.
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30
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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: 4] [Impact Index Per Article: 0.8] [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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31
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Battiato S, Wu S, Zannier V, Bertoni A, Goldoni G, Li A, Xiao S, Han XD, Beltram F, Sorba L, Xu X, Rossella F. Polychromatic emission in a wide energy range from InP-InAs-InP multi-shell nanowires. NANOTECHNOLOGY 2019; 30:194004. [PMID: 30634180 DOI: 10.1088/1361-6528/aafde4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
InP-InAs-InP multi-shell nanowires (NWs) were grown in the wurtzite (WZ) or zincblende (ZB) crystal phase and their photoluminescence (PL) properties were investigated at low temperature (≈6 K) for different measurement geometries. PL emissions from the NWs were carefully studied in a wide energy range from 0.7 to 1.6 eV. The different features observed in the PL spectra for increasing energies are attributed to four distinct emitting domains of these nano-heterostructures: the InAs island (axially grown), the thin InAs capping shell (radially grown), the crystal-phase quantum disks arising from the coexistence of InP ZB and WZ segments in the same NW, and the InP portions of the NW. These results provide a useful frame for the rational implementation of InP-InAs-InP multi-shell NWs containing various quantum confined domains as polychromatic optically active components in nanodevices for quantum information and communication technologies.
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Affiliation(s)
- S Battiato
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, I-56217 Pisa, Italy
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32
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Lehmann S, Wallentin J, Mårtensson EK, Ek M, Deppert K, Dick KA, Borgström MT. Simultaneous Growth of Pure Wurtzite and Zinc Blende Nanowires. NANO LETTERS 2019; 19:2723-2730. [PMID: 30888174 DOI: 10.1021/acs.nanolett.9b01007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The opportunity to engineer III-V nanowires in wurtzite and zinc blende crystal structure allows for exploring properties not conventionally available in the bulk form as well as opening the opportunity for use of additional degrees of freedom in device fabrication. However, the fundamental understanding of the nature of polytypism in III-V nanowire growth is still lacking key ingredients to be able to connect the results of modeling and experiments. Here we show InP nanowires of both pure wurtzite and pure zinc blende grown simultaneously on the same InP [100]-oriented substrate. We find wurtzite nanowires to grow along [Formula: see text] and zinc blende counterparts along [Formula: see text]. Further, we discuss the nucleation, growth, and polytypism of our nanowires against the background of existing theory. Our results demonstrate, first, that the crystal growth conditions for wurtzite and zinc blende nanowire growth are not mutually exclusive and, second, that the interface energies predominantly determine the crystal structure of the nanowires.
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Affiliation(s)
- Sebastian Lehmann
- Solid State Physics and NanoLund , Lund University , Box 118, S-221 00 Lund , Sweden
| | - Jesper Wallentin
- Solid State Physics and NanoLund , Lund University , Box 118, S-221 00 Lund , Sweden
- Synchrotron Radiation Research and NanoLund , Box 118, S-221 00 Lund , Sweden
| | - Erik K Mårtensson
- Solid State Physics and NanoLund , Lund University , Box 118, S-221 00 Lund , Sweden
| | - Martin Ek
- Centre for Analysis and Synthesis , Lund University , Box 124, 221 00 , Lund , Sweden
| | - Knut Deppert
- Solid State Physics and NanoLund , Lund University , Box 118, S-221 00 Lund , Sweden
| | - Kimberly A Dick
- Solid State Physics and NanoLund , Lund University , Box 118, S-221 00 Lund , Sweden
- Centre for Analysis and Synthesis , Lund University , Box 124, 221 00 , Lund , Sweden
| | - Magnus T Borgström
- Solid State Physics and NanoLund , Lund University , Box 118, S-221 00 Lund , Sweden
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33
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Francaviglia L, Tütüncüoglu G, Matteini F, Morral AFI. Tuning adatom mobility and nanoscale segregation by twin formation and polytypism. NANOTECHNOLOGY 2019; 30:054006. [PMID: 30517084 DOI: 10.1088/1361-6528/aaefdd] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Nanoscale variations in the composition of an Al x Ga1-x As shell around a GaAs nanowire affect the nanowire functionality and can lead to the formation of localized quantum emitters. These composition fluctuations can be the consequence of variations of crystal phase and/or nanoscale adatom mobility. By applying electron-microscopy-related techniques we correlate the optical, compositional and structural properties at the nanoscale on the same object. The results indicate a clear correlation between the twin density in the nanowire and the quantum-emitter density as well as a significant redshift in the emission. We propose that twinning increases nanoscale segregation effects in ternary alloys. An additional redshift in the emission can be explained by the staggered band alignment between wurtzite and zinc-blende phases. This work opens new avenues in the achievement of homogeneous ternary and quaternary alloys in nanowires and in the engineering of the segregation effects at the nanoscale.
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Affiliation(s)
- Luca Francaviglia
- Laboratoire des Matériaux Semiconducteurs, Institut des Matériaux, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
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34
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Corfdir P, Marquardt O, Lewis RB, Sinito C, Ramsteiner M, Trampert A, Jahn U, Geelhaar L, Brandt O, Fomin VM. Excitonic Aharonov-Bohm Oscillations in Core-Shell Nanowires. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1805645. [PMID: 30461088 DOI: 10.1002/adma.201805645] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 10/15/2018] [Indexed: 06/09/2023]
Abstract
Phase coherence in nanostructures is at the heart of a wide range of quantum effects such as Josephson oscillations between exciton-polariton condensates in microcavities, conductance quantization in 1D ballistic transport, or the optical (excitonic) Aharonov-Bohm effect in semiconductor quantum rings. These effects only occur in structures of the highest perfection. The 2D semiconductor heterostructures required for the observation of Aharonov-Bohm oscillations have proved to be particularly demanding, since interface roughness or alloy fluctuations cause a loss of the spatial phase coherence of excitons, and ultimately induce exciton localization. Experimental work in this field has so far relied on either self-assembled ring structures with very limited control of shape and dimension or on lithographically defined nanorings that suffer from the detrimental effects of free surfaces. Here, it is demonstrated that nanowires are an ideal platform for studies of the Aharonov-Bohm effect of neutral and charged excitons, as they facilitate the controlled fabrication of nearly ideal quantum rings by combining all-binary radial heterostructures with axial crystal-phase quantum structures. Thanks to the atomically flat interfaces and the absence of alloy disorder, excitonic phase coherence is preserved even in rings with circumferences as large as 200 nm.
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Affiliation(s)
- Pierre Corfdir
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V., Hausvogteiplatz 5-7, 10117, Berlin, Germany
| | - Oliver Marquardt
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V., Hausvogteiplatz 5-7, 10117, Berlin, Germany
- Weierstraß-Institut für Angewandte Analysis und Stochastik, Leibniz-Institut im Forschungsverbund Berlin e. V., Mohrenstraße 39, 10117, Berlin, Germany
| | - Ryan B Lewis
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V., Hausvogteiplatz 5-7, 10117, Berlin, Germany
| | - Chiara Sinito
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V., Hausvogteiplatz 5-7, 10117, Berlin, Germany
| | - Manfred Ramsteiner
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V., Hausvogteiplatz 5-7, 10117, Berlin, Germany
| | - Achim Trampert
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V., Hausvogteiplatz 5-7, 10117, Berlin, Germany
| | - Uwe Jahn
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V., Hausvogteiplatz 5-7, 10117, Berlin, Germany
| | - Lutz Geelhaar
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V., Hausvogteiplatz 5-7, 10117, Berlin, Germany
| | - Oliver Brandt
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V., Hausvogteiplatz 5-7, 10117, Berlin, Germany
| | - Vladimir M Fomin
- Institute for Integrative Nanosciences, Leibniz IFW Dresden, Helmholtzstraße 20, 01069, Dresden, Germany
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35
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Li C, Habler G, Griffiths T, Rečnik A, Jeřábek P, Götze LC, Mangler C, Pennycook TJ, Meyer J, Abart R. Structure evolution of h.c.p./c.c.p. metal oxide interfaces in solid-state reactions. ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES 2018; 74:466-480. [PMID: 30182934 DOI: 10.1107/s205327331800757x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 05/20/2018] [Indexed: 11/10/2022]
Abstract
The structure of crystalline interfaces plays an important role in solid-state reactions. The Al2O3/MgAl2O4/MgO system provides an ideal model system for investigating the mechanisms underlying the migration of interfaces during interface reaction. MgAl2O4 layers have been grown between Al2O3 and MgO, and the atomic structure of Al2O3/MgAl2O4 interfaces at different growth stages was characterized using aberration-corrected scanning transmission electron microscopy. The oxygen sublattice transforms from hexagonal close-packed (h.c.p.) stacking in Al2O3 to cubic close-packed (c.c.p.) stacking in MgAl2O4. Partial dislocations associated with steps are observed at the interface. At the reaction-controlled early growth stages, such partial dislocations coexist with the edge dislocations. However, at the diffusion-controlled late growth stages, such partial dislocations are dominant. The observed structures indicate that progression of the Al2O3/MgAl2O4 interface into Al2O3 is accomplished by the glide of partial dislocations accompanied by the exchange of Al3+ and Mg2+ cations. The interface migration may be envisaged as a plane-by-plane zipper-like motion, which repeats along the interface facilitating its propagation. MgAl2O4 grains can adopt two crystallographic orientations with a twinning orientation relationship, and grow by dislocations gliding in opposite directions. Where the oppositely propagating partial dislocations and interface steps meet, interlinked twin boundaries and incoherent Σ3 grain boundaries form. The newly grown MgAl2O4 grains compete with each other, leading to a growth selection and successive coarsening of the MgAl2O4 grains. This understanding could help to interpret the interface reaction or phase transformation of a wide range of materials that exhibit a similar h.c.p./c.c.p. transition.
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Affiliation(s)
- C Li
- Department of Lithospheric Research, University of Vienna, Althanstrasse 14, Vienna, 1090, Austria
| | - G Habler
- Department of Lithospheric Research, University of Vienna, Althanstrasse 14, Vienna, 1090, Austria
| | - T Griffiths
- Department of Lithospheric Research, University of Vienna, Althanstrasse 14, Vienna, 1090, Austria
| | - A Rečnik
- Department for Nanostructured Materials, Joǽef Stefan Institute, Jamova cesta 39, Ljubljana, SI-1000, Slovenia
| | - P Jeřábek
- Institute of Petrology and Structural Geology, Faculty of Science, Charles University, Albertov 6, Prague, 12843, Czech Republic
| | - L C Götze
- Institute of Geological Sciences, Freie Universität Berlin, Malteserstrasse 74-100, Berlin, 12249, Germany
| | - C Mangler
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, Vienna, 1090, Austria
| | - T J Pennycook
- Stuttgart Center for Electron Microscopy, Max Planck Institute for Solid State Research, Heisenbergstrasse 1, Stuttgart, 70569, Germany
| | - J Meyer
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, Vienna, 1090, Austria
| | - R Abart
- Department of Lithospheric Research, University of Vienna, Althanstrasse 14, Vienna, 1090, Austria
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36
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Gagliano L, Kruijsse M, Schefold JDD, Belabbes A, Verheijen MA, Meuret S, Koelling S, Polman A, Bechstedt F, Haverkort J, Bakkers E. Efficient Green Emission from Wurtzite Al xIn 1- xP Nanowires. NANO LETTERS 2018; 18:3543-3549. [PMID: 29701976 PMCID: PMC6002781 DOI: 10.1021/acs.nanolett.8b00621] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 04/18/2018] [Indexed: 06/01/2023]
Abstract
Direct band gap III-V semiconductors, emitting efficiently in the amber-green region of the visible spectrum, are still missing, causing loss in efficiency in light emitting diodes operating in this region, a phenomenon known as the "green gap". Novel geometries and crystal symmetries however show strong promise in overcoming this limit. Here we develop a novel material system, consisting of wurtzite Al xIn1- xP nanowires, which is predicted to have a direct band gap in the green region. The nanowires are grown with selective area metalorganic vapor phase epitaxy and show wurtzite crystal purity from transmission electron microscopy. We show strong light emission at room temperature between the near-infrared 875 nm (1.42 eV) and the "pure green" 555 nm (2.23 eV). We investigate the band structure of wurtzite Al xIn1- xP using time-resolved and temperature-dependent photoluminescence measurements and compare the experimental results with density functional theory simulations, obtaining excellent agreement. Our work paves the way for high-efficiency green light emitting diodes based on wurtzite III-phosphide nanowires.
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Affiliation(s)
- L. Gagliano
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB Eindhoven, The Netherlands
| | - M. Kruijsse
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB Eindhoven, The Netherlands
| | - J. D. D. Schefold
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - A. Belabbes
- Institut
für Festkörpertheorie und -optik, Friedrich-Schiller-Universitat, Max-Wien-Platz 1, D-07743 Jena, Germany
| | - M. A. Verheijen
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB Eindhoven, The Netherlands
- Philips
Innovation Laboratories Eindhoven, High Tech Campus 11, 5656AE Eindhoven, The Netherlands
| | - S. Meuret
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - S. Koelling
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB Eindhoven, The Netherlands
| | - A. Polman
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - F. Bechstedt
- Institut
für Festkörpertheorie und -optik, Friedrich-Schiller-Universitat, Max-Wien-Platz 1, D-07743 Jena, Germany
| | - J.E.M. Haverkort
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB Eindhoven, The Netherlands
| | - E.P.A.M. Bakkers
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB Eindhoven, The Netherlands
- Kavli
Institute of Nanoscience, Delft University
of Technology, 2600 GA Delft, The Netherlands
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37
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Ben Sedrine N, Ribeiro-Andrade R, Gustafsson A, Soares MR, Bourgard J, Teixeira JP, Salomé PMP, Correia MR, Moreira MVB, De Oliveira AG, González JC, Leitão JP. Fluctuating potentials in GaAs:Si nanowires: critical reduction of the influence of polytypism on the electronic structure. NANOSCALE 2018; 10:3697-3708. [PMID: 29388656 DOI: 10.1039/c7nr08395e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In this work, the effects of Si doping in GaAs nanowires (NWs) grown on GaAs (111)B by molecular beam epitaxy with different Si doping levels (nominal free carrier concentrations of 1 × 1016, 8 × 1016, 1 × 1018 and 5 × 1018 cm-3) are deeply investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), grazing incidence X-ray diffraction (GID), photoluminescence (PL) and cathadoluminescence (CL). TEM results reveal a mixture of wurtzite (WZ) and zinc-blende (ZB) segments along the NW axis independently of the Si doping levels. GID measurements suggest a slight increase of the ZB fraction with the Si doping. Low temperature PL and CL spectra exhibit sharp lines in the energy range 1.41-1.48 eV, for the samples with lower Si doping levels. However, the emission intensity increases and is accompanied by a clear broadening of the observed lines for the samples with higher Si doping levels. The staggered type-II band alignment only determines the optical properties of the lower doping levels in GaAs:Si NWs. For the higher Si doping levels, the electronic energy level structure of the NWs is determined by electrostatic fluctuating potentials intimately related to the amphoteric behavior of the Si dopant in GaAs. For the heavily doped NWs, the estimated depth of the potential wells is ∼96-117 meV. Our results reveal that the occurrence of the fluctuating potentials is not dependent on the crystalline phase and shows that the limitation imposed by the polytypism can be overcome.
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Affiliation(s)
- N Ben Sedrine
- Departamento de Física and I3N, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
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38
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Corfdir P, Li H, Marquardt O, Gao G, Molas MR, Zettler JK, van Treeck D, Flissikowski T, Potemski M, Draxl C, Trampert A, Fernández-Garrido S, Grahn HT, Brandt O. Crystal-Phase Quantum Wires: One-Dimensional Heterostructures with Atomically Flat Interfaces. NANO LETTERS 2018; 18:247-254. [PMID: 29257698 DOI: 10.1021/acs.nanolett.7b03997] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In semiconductor quantum-wire heterostructures, interface roughness leads to exciton localization and to a radiative decay rate much smaller than that expected for structures with flat interfaces. Here, we uncover the electronic and optical properties of the one-dimensional extended defects that form at the intersection between stacking faults and inversion domain boundaries in GaN nanowires. We show that they act as crystal-phase quantum wires, a novel one-dimensional quantum system with atomically flat interfaces. These quantum wires efficiently capture excitons whose radiative decay gives rise to an optical doublet at 3.36 eV at 4.2 K. The binding energy of excitons confined in crystal-phase quantum wires is measured to be more than twice larger than that of the bulk. As a result of their unprecedented interface quality, these crystal-phase quantum wires constitute a model system for the study of one-dimensional excitons.
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Affiliation(s)
- Pierre Corfdir
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V. , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - Hong Li
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V. , Hausvogteiplatz 5-7, 10117 Berlin, Germany
- Institut für Physik and IRIS Adlershof, Humboldt-Universität zu Berlin , Zum Großen Windkanal 6, 12489 Berlin, Germany
| | - Oliver Marquardt
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V. , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - Guanhui Gao
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V. , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - Maciej R Molas
- Laboratoire National des Champs Magnétiques Intenses, CNRS-UGA-UPS-INSA-EMFL , 25 avenue des Martyrs, 38042 Grenoble, France
| | - Johannes K Zettler
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V. , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - David van Treeck
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V. , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - Timur Flissikowski
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V. , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - Marek Potemski
- Laboratoire National des Champs Magnétiques Intenses, CNRS-UGA-UPS-INSA-EMFL , 25 avenue des Martyrs, 38042 Grenoble, France
| | - Claudia Draxl
- Institut für Physik and IRIS Adlershof, Humboldt-Universität zu Berlin , Zum Großen Windkanal 6, 12489 Berlin, Germany
| | - Achim Trampert
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V. , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - Sergio Fernández-Garrido
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V. , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - Holger T Grahn
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V. , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - Oliver Brandt
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V. , Hausvogteiplatz 5-7, 10117 Berlin, Germany
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39
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Himwas C, Collin S, Rale P, Chauvin N, Patriarche G, Oehler F, Julien FH, Travers L, Harmand JC, Tchernycheva M. In situ passivation of GaAsP nanowires. NANOTECHNOLOGY 2017; 28:495707. [PMID: 29057754 DOI: 10.1088/1361-6528/aa9533] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We report on the structural and optical properties of GaAsP nanowires (NWs) grown by molecular-beam epitaxy. By adjusting the alloy composition in the NWs, the transition energy was tuned to the optimal value required for tandem III-V/silicon solar cells. We discovered that an unintentional shell was also formed during the GaAsP NW growth. The NW surface was passivated by an in situ deposition of a radial Ga(As)P shell. Different shell compositions and thicknesses were investigated. We demonstrate that the optimal passivation conditions for GaAsP NWs (with a gap of 1.78 eV) are obtained with a 5 nm thick GaP shell. This passivation enhances the luminescence intensity of the NWs by 2 orders of magnitude and yields a longer luminescence decay. The luminescence dynamics changes from single exponential decay with a 4 ps characteristic time in non-passivated NWs to a bi-exponential decay with characteristic times of 85 and 540 ps in NWs with GaP shell passivation.
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Affiliation(s)
- C Himwas
- Centre de Nanosciences et de Nanotechnologies-site Orsay, UMR 9001 CNRS, Univ. Paris Sud, Univ. Paris-Saclay, Bât 220, rue André Ampère, F-91405 Orsay, France
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40
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Ullah AR, Joyce HJ, Tan HH, Jagadish C, Micolich AP. The influence of atmosphere on the performance of pure-phase WZ and ZB InAs nanowire transistors. NANOTECHNOLOGY 2017; 28:454001. [PMID: 29039362 DOI: 10.1088/1361-6528/aa8e23] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We compare the characteristics of phase-pure MOCVD grown ZB and WZ InAs nanowire transistors in several atmospheres: air, dry pure N2 and O2, and N2 bubbled through liquid H2O and alcohols to identify whether phase-related structural/surface differences affect their response. Both WZ and ZB give poor gate characteristics in dry state. Adsorption of polar species reduces off-current by 2-3 orders of magnitude, increases on-off ratio and significantly reduces sub-threshold slope. The key difference is the greater sensitivity of WZ to low adsorbate level. We attribute this to facet structure and its influence on the separation between conduction electrons and surface adsorption sites. We highlight the important role adsorbed species play in nanowire device characterisation. WZ is commonly thought superior to ZB in InAs nanowire transistors. We show this is an artefact of the moderate humidity found in ambient laboratory conditions: WZ and ZB perform equally poorly in the dry gas limit yet equally well in the wet gas limit. We also highlight the vital role density-lowering disorder has in improving gate characteristics, be it stacking faults in mixed-phase WZ or surface adsorbates in pure-phase nanowires.
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Affiliation(s)
- A R Ullah
- School of Physics, University of New South Wales, Sydney NSW 2052, Australia
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41
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Knutsson JV, Lehmann S, Hjort M, Lundgren E, Dick KA, Timm R, Mikkelsen A. Electronic Structure Changes Due to Crystal Phase Switching at the Atomic Scale Limit. ACS NANO 2017; 11:10519-10528. [PMID: 28960985 DOI: 10.1021/acsnano.7b05873] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The perfect switching between crystal phases with different electronic structure in III-V nanowires allows for the design of superstructures with quantum wells only a single atomic layer wide. However, it has only been indirectly inferred how the electronic structure will vary down to the smallest possible crystal segments. We use low-temperature scanning tunneling microscopy and spectroscopy to directly probe the electronic structure of Zinc blende (Zb) segments in Wurtzite (Wz) InAs nanowires with atomic-scale precision. We find that the major features in the band structure change abruptly down to a single atomic layer level. Distinct Zb electronic structure signatures are observed on both the conduction and valence band sides for the smallest possible Zb segment: a single InAs bilayer. We find evidence of confined states in the region of both single and double bilayer Zb segments indicative of the formation of crystal segment quantum wells due to the smaller band gap of Zb as compared to Wz. In contrast to the internal electronic structure of the nanowire, surface states located in the band gap were found to be only weakly influenced by the presence of the smallest Zb segments. Our findings directly demonstrate the feasibility of crystal phase switching for the ultimate limit of atomistic band structure engineering of quantum confined structures. Further, it indicates that band gap values obtained for the bulk are reasonable to use even for the smallest crystal segments. However, we also find that the suppression of surface and interface states could be necessary in the use of this effect for engineering of future electronic devices.
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Affiliation(s)
| | - Sebastian Lehmann
- Department of Physics & NanoLund, Lund University , P.O. Box 118, 22 100 Lund, Sweden
| | - Martin Hjort
- Department of Materials Science and Engineering, Stanford University , Stanford, California 94305, United States
| | - Edvin Lundgren
- Department of Physics & NanoLund, Lund University , P.O. Box 118, 22 100 Lund, Sweden
| | - Kimberly A Dick
- Department of Physics & NanoLund, Lund University , P.O. Box 118, 22 100 Lund, Sweden
- Center for Analysis and Synthesis, Lund University , P.O. Box 124, 221 00 Lund, Sweden
| | - Rainer Timm
- Department of Physics & NanoLund, Lund University , P.O. Box 118, 22 100 Lund, Sweden
| | - Anders Mikkelsen
- Department of Physics & NanoLund, Lund University , P.O. Box 118, 22 100 Lund, Sweden
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42
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Assali S, Lähnemann J, Vu TTT, Jöns KD, Gagliano L, Verheijen MA, Akopian N, Bakkers EPAM, Haverkort JEM. Crystal Phase Quantum Well Emission with Digital Control. NANO LETTERS 2017; 17:6062-6068. [PMID: 28892396 PMCID: PMC5642001 DOI: 10.1021/acs.nanolett.7b02489] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 09/06/2017] [Indexed: 05/31/2023]
Abstract
One of the major challenges in the growth of quantum well and quantum dot heterostructures is the realization of atomically sharp interfaces. Nanowires provide a new opportunity to engineer the band structure as they facilitate the controlled switching of the crystal structure between the zinc-blende (ZB) and wurtzite (WZ) phases. Such a crystal phase switching results in the formation of crystal phase quantum wells (CPQWs) and quantum dots (CPQDs). For GaP CPQWs, the inherent electric fields due to the discontinuity of the spontaneous polarization at the WZ/ZB junctions lead to the confinement of both types of charge carriers at the opposite interfaces of the WZ/ZB/WZ structure. This confinement leads to a novel type of transition across a ZB flat plate barrier. Here, we show digital tuning of the visible emission of WZ/ZB/WZ CPQWs in a GaP nanowire by changing the thickness of the ZB barrier. The energy spacing between the sharp emission lines is uniform and is defined by the addition of single ZB monolayers. The controlled growth of identical quantum wells with atomically flat interfaces at predefined positions featuring digitally tunable discrete emission energies may provide a new route to further advance entangled photons in solid state quantum systems.
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Affiliation(s)
- S. Assali
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB, Eindhoven, The Netherlands
| | - J. Lähnemann
- Paul-Drude-Institut
für Festkörperelektronik, Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - T. T. T. Vu
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB, Eindhoven, The Netherlands
| | - K. D. Jöns
- Kavli
Institute of Nanoscience, Delft University
of Technology, 2600 GA, Delft, The Netherlands
| | - L. Gagliano
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB, Eindhoven, The Netherlands
| | - M. A. Verheijen
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB, Eindhoven, The Netherlands
- Philips
Innovation Services Eindhoven, High Tech Campus 11, 5656 AE, Eindhoven, The
Netherlands
| | - N. Akopian
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB, Eindhoven, The Netherlands
- Kavli
Institute of Nanoscience, Delft University
of Technology, 2600 GA, Delft, The Netherlands
| | - E. P. A. M. Bakkers
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB, Eindhoven, The Netherlands
- Kavli
Institute of Nanoscience, Delft University
of Technology, 2600 GA, Delft, The Netherlands
| | - J. E. M. Haverkort
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB, Eindhoven, The Netherlands
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43
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On-chip single photon filtering and multiplexing in hybrid quantum photonic circuits. Nat Commun 2017; 8:379. [PMID: 28855499 PMCID: PMC5577278 DOI: 10.1038/s41467-017-00486-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 07/03/2017] [Indexed: 12/24/2022] Open
Abstract
Quantum light plays a pivotal role in modern science and future photonic applications. Since the advent of integrated quantum nanophotonics different material platforms based on III–V nanostructures-, colour centers-, and nonlinear waveguides as on-chip light sources have been investigated. Each platform has unique advantages and limitations; however, all implementations face major challenges with filtering of individual quantum states, scalable integration, deterministic multiplexing of selected quantum emitters, and on-chip excitation suppression. Here we overcome all of these challenges with a hybrid and scalable approach, where single III–V quantum emitters are positioned and deterministically integrated in a complementary metal–oxide–semiconductor-compatible photonic circuit. We demonstrate reconfigurable on-chip single-photon filtering and wavelength division multiplexing with a foot print one million times smaller than similar table-top approaches, while offering excitation suppression of more than 95 dB and efficient routing of single photons over a bandwidth of 40 nm. Our work marks an important step to harvest quantum optical technologies’ full potential. Combining different integration platforms on the same chip is currently one of the main challenges for quantum technologies. Here, Elshaari et al. show III-V Quantum Dots embedded in nanowires operating in a CMOS compatible circuit, with controlled on-chip filtering and tunable routing.
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44
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Gagliano L, Belabbes A, Albani M, Assali S, Verheijen MA, Miglio L, Bechstedt F, Haverkort JEM, Bakkers EPAM. Pseudodirect to Direct Compositional Crossover in Wurtzite GaP/In xGa 1-xP Core-Shell Nanowires. NANO LETTERS 2016; 16:7930-7936. [PMID: 27960532 DOI: 10.1021/acs.nanolett.6b04242] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Thanks to their uniqueness, nanowires allow the realization of novel semiconductor crystal structures with yet unexplored properties, which can be key to overcome current technological limits. Here we develop the growth of wurtzite GaP/InxGa1-xP core-shell nanowires with tunable indium concentration and optical emission in the visible region from 590 nm (2.1 eV) to 760 nm (1.6 eV). We demonstrate a pseudodirect (Γ8c-Γ9v) to direct (Γ7c-Γ9v) transition crossover through experimental and theoretical approach. Time resolved and temperature dependent photoluminescence measurements were used, which led to the observation of a steep change in carrier lifetime and temperature dependence by respectively one and 3 orders of magnitude in the range 0.28 ± 0.04 ≤ x ≤ 0.41 ± 0.04. Our work reveals the electronic properties of wurtzite InxGa1-xP.
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Affiliation(s)
- L Gagliano
- Department of Applied Physics, Eindhoven University of Technology , 5600 MB Eindhoven, The Netherlands
| | - A Belabbes
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Saudi Arabia
- Institut für Festkörpertheorie und -optik, Friedrich-Schiller-Universitat , Max-Wien-Platz 1, D-07743 Jena, Germany
| | - M Albani
- L-NESS and Department of Materials Science, University of Milano Bicocca , 20125, Milano, Italy
| | - S Assali
- Department of Applied Physics, Eindhoven University of Technology , 5600 MB Eindhoven, The Netherlands
| | - M A Verheijen
- Department of Applied Physics, Eindhoven University of Technology , 5600 MB Eindhoven, The Netherlands
- Philips Innovation Laboratories Eindhoven , High Tech Campus 11, 5656AE Eindhoven, The Netherlands
| | - L Miglio
- L-NESS and Department of Materials Science, University of Milano Bicocca , 20125, Milano, Italy
| | - F Bechstedt
- Institut für Festkörpertheorie und -optik, Friedrich-Schiller-Universitat , Max-Wien-Platz 1, D-07743 Jena, Germany
| | - J E M Haverkort
- Department of Applied Physics, Eindhoven University of Technology , 5600 MB Eindhoven, The Netherlands
| | - E P A M Bakkers
- Department of Applied Physics, Eindhoven University of Technology , 5600 MB Eindhoven, The Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology , 2600 GA Delft, The Netherlands
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45
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Wang F, Loomis RA, Buhro WE. Spectroscopic Properties of Phase-Pure and Polytypic Colloidal Semiconductor Quantum Wires. ACS NANO 2016; 10:9745-9754. [PMID: 27666893 DOI: 10.1021/acsnano.6b06091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We report ensemble extinction and photoluminesence spectra for colloidal CdTe quantum wires (QWs) with nearly phase-pure, defect-free wurtzite (WZ) structure, having spectral line widths comparable to the best ensemble or single quantum-dot values, to the single polytypic (having WZ and zinc blende (ZB) alternations) QW values, and to those of two-dimensional quantum belts or platelets. The electronic structures determined from the multifeatured extinction spectra are in excellent agreement with the theoretical results of WZ QWs having the same crystallographic orientation. Optical properties of polytypic QWs of like diameter and diameter distribution are provided for comparison, which exhibit smaller bandgaps and broader spectral line widths. The nonperiodic WZ-ZB alternations are found to generate non-negligible shifts of the bandgap to intermediate energies between the quantum-confined WZ and ZB energies. The alternations and variations in the domain sizes result in inhomogeneous spectral line width broadening that may be more significant than that arising from the 12-13% diameter distributions within the QW ensembles.
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Affiliation(s)
- Fudong Wang
- Department of Chemistry, Washington University , St. Louis, Missouri 63130-4899, United States
| | - Richard A Loomis
- Department of Chemistry, Washington University , St. Louis, Missouri 63130-4899, United States
| | - William E Buhro
- Department of Chemistry, Washington University , St. Louis, Missouri 63130-4899, United States
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46
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Timofeeva M, Bouravleuv A, Cirlin G, Shtrom I, Soshnikov I, Reig Escalé M, Sergeyev A, Grange R. Polar Second-Harmonic Imaging to Resolve Pure and Mixed Crystal Phases along GaAs Nanowires. NANO LETTERS 2016; 16:6290-6297. [PMID: 27657488 DOI: 10.1021/acs.nanolett.6b02592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
In this work, we report an optical method for characterizing crystal phases along single-semiconductor III-V nanowires based on the measurement of polarization-dependent second-harmonic generation. This powerful imaging method is based on a per-pixel analysis of the second-harmonic-generated signal on the incoming excitation polarization. The dependence of the second-harmonic generation responses on the nonlinear second-order susceptibility tensor allows the distinguishing of areas of pure wurtzite, zinc blende, and mixed and rotational twins crystal structures in individual nanowires. With a far-field nonlinear optical microscope, we recorded the second-harmonic generation in GaAs nanowires and precisely determined their various crystal structures by analyzing the polar response for each pixel of the images. The predicted crystal phases in GaAs nanowire are confirmed with scanning transmission electron and high-resolution transmission electron measurements. The developed method of analyzing the nonlinear polar response of each pixel can be used for an investigation of nanowire crystal structure that is quick, sensitive to structural transitions, nondestructive, and on-the-spot. It can be applied for the crystal phase characterization of nanowires built into optoelectronic devices in which electron microscopy cannot be performed (for example, in lab-on-a-chip devices). Moreover, this method is not limited to GaAs nanowires but can be used for other nonlinear optical nanostructures.
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Affiliation(s)
- Maria Timofeeva
- Optical Nanomaterial Group, Institute for Quantum Electronics, Department of Physics, ETH Zurich , Auguste-Piccard Hof 1, 8093 Zurich, Switzerland
- ITMO University , Kronverkskiy 49, 197101 Saint Petersburg, Russia
| | - Alexei Bouravleuv
- St. Petersburg Academic University , Khlopina 8/3, 194021 Saint Petersburg, Russia
- Ioffe Institute , Politekhnicheskaya 29, 194021 Saint Petersburg, Russia
| | - George Cirlin
- St. Petersburg Academic University , Khlopina 8/3, 194021 Saint Petersburg, Russia
- ITMO University , Kronverkskiy 49, 197101 Saint Petersburg, Russia
- Ioffe Institute , Politekhnicheskaya 29, 194021 Saint Petersburg, Russia
| | - Igor Shtrom
- St. Petersburg Academic University , Khlopina 8/3, 194021 Saint Petersburg, Russia
- Ioffe Institute , Politekhnicheskaya 29, 194021 Saint Petersburg, Russia
| | - Ilya Soshnikov
- St. Petersburg Academic University , Khlopina 8/3, 194021 Saint Petersburg, Russia
- Ioffe Institute , Politekhnicheskaya 29, 194021 Saint Petersburg, Russia
| | - Marc Reig Escalé
- Optical Nanomaterial Group, Institute for Quantum Electronics, Department of Physics, ETH Zurich , Auguste-Piccard Hof 1, 8093 Zurich, Switzerland
| | - Anton Sergeyev
- Optical Nanomaterial Group, Institute for Quantum Electronics, Department of Physics, ETH Zurich , Auguste-Piccard Hof 1, 8093 Zurich, Switzerland
| | - Rachel Grange
- Optical Nanomaterial Group, Institute for Quantum Electronics, Department of Physics, ETH Zurich , Auguste-Piccard Hof 1, 8093 Zurich, Switzerland
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47
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Kinzel JB, Schülein FJR, Weiß M, Janker L, Bühler DD, Heigl M, Rudolph D, Morkötter S, Döblinger M, Bichler M, Abstreiter G, Finley JJ, Wixforth A, Koblmüller G, Krenner HJ. The Native Material Limit of Electron and Hole Mobilities in Semiconductor Nanowires. ACS NANO 2016; 10:4942-4953. [PMID: 27007813 DOI: 10.1021/acsnano.5b07639] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- Jörg B Kinzel
- Lehrstuhl für Experimentalphysik 1 and Augsburg Centre for Innovative Technologies (ACIT), Universität Augsburg , Universitätsstraße 1, 86159 Augsburg, Germany
- Nanosystems Initiative Munich (NIM) , Schellingstraße 4, 80339 München, Germany
| | - Florian J R Schülein
- Lehrstuhl für Experimentalphysik 1 and Augsburg Centre for Innovative Technologies (ACIT), Universität Augsburg , Universitätsstraße 1, 86159 Augsburg, Germany
- Nanosystems Initiative Munich (NIM) , Schellingstraße 4, 80339 München, Germany
| | - Matthias Weiß
- Lehrstuhl für Experimentalphysik 1 and Augsburg Centre for Innovative Technologies (ACIT), Universität Augsburg , Universitätsstraße 1, 86159 Augsburg, Germany
- Nanosystems Initiative Munich (NIM) , Schellingstraße 4, 80339 München, Germany
| | - Lisa Janker
- Lehrstuhl für Experimentalphysik 1 and Augsburg Centre for Innovative Technologies (ACIT), Universität Augsburg , Universitätsstraße 1, 86159 Augsburg, Germany
- Nanosystems Initiative Munich (NIM) , Schellingstraße 4, 80339 München, Germany
| | - Dominik D Bühler
- Lehrstuhl für Experimentalphysik 1 and Augsburg Centre for Innovative Technologies (ACIT), Universität Augsburg , Universitätsstraße 1, 86159 Augsburg, Germany
| | - Michael Heigl
- Lehrstuhl für Experimentalphysik 1 and Augsburg Centre for Innovative Technologies (ACIT), Universität Augsburg , Universitätsstraße 1, 86159 Augsburg, Germany
| | - Daniel Rudolph
- Nanosystems Initiative Munich (NIM) , Schellingstraße 4, 80339 München, Germany
- Walter Schottky Institut and Physik Department E24, Technische Universität München , Am Coulombwall 4, 85748 Garching, Germany
| | - Stefanie Morkötter
- Nanosystems Initiative Munich (NIM) , Schellingstraße 4, 80339 München, Germany
- Walter Schottky Institut and Physik Department E24, Technische Universität München , Am Coulombwall 4, 85748 Garching, Germany
| | - Markus Döblinger
- Department of Chemistry, Ludwig-Maximilians-Universität München , 81377 München, Germany
- Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität München , Geschwister-Scholl-Platz 1, 80539 München, Germany
| | - Max Bichler
- Walter Schottky Institut and Physik Department E24, Technische Universität München , Am Coulombwall 4, 85748 Garching, Germany
| | - Gerhard Abstreiter
- Nanosystems Initiative Munich (NIM) , Schellingstraße 4, 80339 München, Germany
- Walter Schottky Institut and Physik Department E24, Technische Universität München , Am Coulombwall 4, 85748 Garching, Germany
- Institute for Advanced Study (IAS), Technische Universität München , Lichtenbergstraße 2a, 85748 Garching, Germany
| | - Jonathan J Finley
- Nanosystems Initiative Munich (NIM) , Schellingstraße 4, 80339 München, Germany
- Walter Schottky Institut and Physik Department E24, Technische Universität München , Am Coulombwall 4, 85748 Garching, Germany
| | - Achim Wixforth
- Lehrstuhl für Experimentalphysik 1 and Augsburg Centre for Innovative Technologies (ACIT), Universität Augsburg , Universitätsstraße 1, 86159 Augsburg, Germany
- Nanosystems Initiative Munich (NIM) , Schellingstraße 4, 80339 München, Germany
- Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität München , Geschwister-Scholl-Platz 1, 80539 München, Germany
| | - Gregor Koblmüller
- Nanosystems Initiative Munich (NIM) , Schellingstraße 4, 80339 München, Germany
- Walter Schottky Institut and Physik Department E24, Technische Universität München , Am Coulombwall 4, 85748 Garching, Germany
| | - Hubert J Krenner
- Lehrstuhl für Experimentalphysik 1 and Augsburg Centre for Innovative Technologies (ACIT), Universität Augsburg , Universitätsstraße 1, 86159 Augsburg, Germany
- Nanosystems Initiative Munich (NIM) , Schellingstraße 4, 80339 München, Germany
- Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität München , Geschwister-Scholl-Platz 1, 80539 München, Germany
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48
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Lindberg C, Whiticar A, Dick K, Sköld N, Nygård J, Bolinsson J. Silver as Seed-Particle Material for GaAs Nanowires--Dictating Crystal Phase and Growth Direction by Substrate Orientation. NANO LETTERS 2016; 16:2181-8. [PMID: 26998550 PMCID: PMC4852989 DOI: 10.1021/acs.nanolett.5b04218] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Revised: 02/29/2016] [Indexed: 05/19/2023]
Abstract
Here we investigate the feasibility of silver as seed-particle material to synthesize GaAs nanowires and show that both crystal phase and growth direction can be controlled by choice of substrate orientation. A (111)B substrate orientation can be used to form vertically aligned wurtzite GaAs nanowires and a (100) substrate orientation to form vertically aligned zinc blende GaAs nanowires. A 45-50% yield of vertical nanowire growth is achieved on the (100) substrate orientation without employing any type of surface modification or nucleation strategy to promote a vertical growth direction. In addition, photoluminescence measurements reveal that the photon emission from the silver seeded wurtzite GaAs nanowires is characterized by a single and narrow emission peak at 1.52 eV.
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Affiliation(s)
- Caroline Lindberg
- Center
for Quantum Devices & Nano-Science Center, Niels Bohr Institute, University of Copenhagen, Nørregade 10, 1165 København, Denmark
| | - Alexander Whiticar
- Center
for Quantum Devices & Nano-Science Center, Niels Bohr Institute, University of Copenhagen, Nørregade 10, 1165 København, Denmark
| | - Kimberly
A. Dick
- Solid State Physics/NanoLund, Center for Analysis and Synthesis, Lund University, 221 00 Lund, Sweden
| | - Niklas Sköld
- Solid State Physics/NanoLund, Center for Analysis and Synthesis, Lund University, 221 00 Lund, Sweden
| | - Jesper Nygård
- Center
for Quantum Devices & Nano-Science Center, Niels Bohr Institute, University of Copenhagen, Nørregade 10, 1165 København, Denmark
| | - Jessica Bolinsson
- Center
for Quantum Devices & Nano-Science Center, Niels Bohr Institute, University of Copenhagen, Nørregade 10, 1165 København, Denmark
- E-mail:
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Interface dynamics and crystal phase switching in GaAs nanowires. Nature 2016; 531:317-22. [PMID: 26983538 PMCID: PMC4876924 DOI: 10.1038/nature17148] [Citation(s) in RCA: 146] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 01/06/2016] [Indexed: 02/07/2023]
Abstract
Controlled formation of non-equilibrium crystal structures is one of the most important challenges in crystal growth. Catalytically-grown nanowires provide an ideal system for studying the fundamental physics of phase selection, while also offering the potential for novel electronic applications based on crystal polytype engineering. Here we image GaAs nanowires during growth as they are switched between polytypes by varying growth conditions. We find striking differences between the growth dynamics of the polytypes, including differences in interface morphology, step flow, and catalyst geometry. We explain the differences, and the phase selection, through a model that relates the catalyst volume, contact angle at the trijunction, and nucleation site of each new layer. This allows us to predict the conditions under which each phase should be preferred, and use these predictions to design GaAs heterostructures. We suggest that these results may apply to phase selection in other nanowire systems.
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Chen Y, Burgess T, An X, Mai YW, Tan HH, Zou J, Ringer SP, Jagadish C, Liao X. Effect of a High Density of Stacking Faults on the Young's Modulus of GaAs Nanowires. NANO LETTERS 2016; 16:1911-1916. [PMID: 26885570 DOI: 10.1021/acs.nanolett.5b05095] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Stacking faults (SFs) are commonly observed crystalline defects in III-V semiconductor nanowires (NWs) that affect a variety of physical properties. Understanding the effect of SFs on NW mechanical properties is critical to NW applications in nanodevices. In this study, the Young's moduli of GaAs NWs with two distinct structures, defect-free single crystalline wurtzite (WZ) and highly defective wurtzite containing a high density of SFs (WZ-SF), are investigated using combined in situ compression transmission electron microscopy and finite element analysis. The Young's moduli of both WZ and WZ-SF GaAs NWs were found to increase with decreasing diameter due to the increasing volume fraction of the native oxide shell. The presence of a high density of SFs was further found to increase the Young's modulus by 13%. This stiffening effect of SFs is attributed to the change in the interatomic bonding configuration at the SFs.
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Affiliation(s)
| | - Tim Burgess
- Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University , Canberra, Australian Capital Territory 2601, Australia
| | | | | | - H Hoe Tan
- Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University , Canberra, Australian Capital Territory 2601, Australia
| | - Jin Zou
- Materials Engineering and Centre for Microscopy and Microanalysis, The University of Queensland , St. Lucia, Queensland 4072, Australia
| | | | - Chennupati Jagadish
- Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University , Canberra, Australian Capital Territory 2601, Australia
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