1
|
Xia Y, Song B, Zhang Z, Wang KL, Li YH, Li N, Chen CH, Chen J, Xing G, Wang ZK. Vertically Concentrated Quantum Wells Enabling Highly Efficient Deep-Blue Perovskite Light-Emitting Diodes. Angew Chem Int Ed Engl 2024; 63:e202403739. [PMID: 38565430 DOI: 10.1002/anie.202403739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 03/27/2024] [Accepted: 04/02/2024] [Indexed: 04/04/2024]
Abstract
Deep-blue perovskite light-emitting diodes (PeLEDs) based on quasi-two-dimensional (quasi-2D) systems exist heightened sensitivity to the domain distribution. The top-down crystallization mode will lead to a vertical gradient distribution of quantum well (QW) structure, which is unfavorable for deep-blue emission. Herein, a thermal gradient annealing treatment is proposed to address the polydispersity issue of vertical QWs in quasi-2D perovskites. The formation of large-n domains at the upper interface of the perovskite film can be effectively inhibited by introducing a low-temperature source in the annealing process. Combined with the utilization of NaBr to inhibit the undesirable n=1 domain, a vertically concentrated QW structure is ultimately attained. As a result, the fabricated device delivers a narrow and stable deep-blue emission at 458 nm with an impressive external quantum efficiency (EQE) of 5.82 %. Green and sky-blue PeLEDs with remarkable EQE of 21.83 % and 17.51 % are also successfully achieved, respectively, by using the same strategy. The findings provide a universal strategy across the entire quasi-2D perovskites, paving the way for future practical application of PeLEDs.
Collapse
Affiliation(s)
- Yu Xia
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China
| | - Bin Song
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China
| | - Zhipeng Zhang
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, 999078 Macao SAR, China
| | - Kai-Li Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China
| | - Yu-Han Li
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China
| | - Nan Li
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China
| | - Chun-Hao Chen
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China
| | - Jing Chen
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China
| | - Guichuan Xing
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, 999078 Macao SAR, China
| | - Zhao-Kui Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China
| |
Collapse
|
2
|
Yuan Q, Huang J, Li A, Lu N, Lu W, Zhu Y, Zhang Z. Engineering Semi-Reversed Quantum Well Photocatalysts for Highly-Efficient Solar-to-Fuels Conversion. Adv Mater 2024; 36:e2311764. [PMID: 38181062 DOI: 10.1002/adma.202311764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 12/29/2023] [Indexed: 01/07/2024]
Abstract
Semiconductor quantum wells (QWs) exhibit high charge-utilization efficiency for light-emitting applications due to their strong charge confinement effect. Inspired by this effect, herein, this work proposes a new idea to significantly improve the photo-generated charge separation for attaining a highly-efficient solar-to-fuels conversion process through "semi-reversing" the conventional QWs to confine only the photo-generated electrons. This electron confinement-improved charge separation is implemented in the well-designed model of the CdS/TiO2/CdS semi-reversed QW (SRQW) structure. The latter is fabricated by selectively assembling CdS quantum dots (QDs) onto the {101} facets (ultra-thin edge regions) of the TiO2 nanosheets (NSs). Upon light excitation, the photo-generated electrons of SRQW can be confined on the TiO2-{101} facets in the vicinity of the CdS/TiO2 hetero-interface. Thereby, the continuous multi-electron injection to the adsorbed reactants on the interfacial active-sites is significantly accelerated. Thus, the CdS/TiO2/CdS SRQW exhibits ≈35.7 and ≈56.0-fold enhancements on the photocatalytic activities for water and CO2 reduction, respectively, compared to those of pure TiO2. Correspondingly, its CH4-product selectivity is increased by ≈180%. This work provides a novel charge separation mechanism, which is of great importance for the design of the next-generation quantum-sized photocatalysts for solar-to-fuels conversion.
Collapse
Affiliation(s)
- Qing Yuan
- Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission, Key Laboratory of Photosensitive Materials and Devices of Liaoning Province, School of Physics and Materials Engineering, Dalian Minzu University, 18 Liaohe West Road, Dalian, 116600, P. R. China
- Dalian Key Laboratory of Low-Dimensional Semiconductor Optoelectronic Materials and Applications, School of Physics and Materials Engineering, Dalian Minzu University, 18 Liaohe West Road, Dalian, 116600, P. R. China
| | - Jindou Huang
- Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission, Key Laboratory of Photosensitive Materials and Devices of Liaoning Province, School of Physics and Materials Engineering, Dalian Minzu University, 18 Liaohe West Road, Dalian, 116600, P. R. China
- Dalian Key Laboratory of Low-Dimensional Semiconductor Optoelectronic Materials and Applications, School of Physics and Materials Engineering, Dalian Minzu University, 18 Liaohe West Road, Dalian, 116600, P. R. China
| | - Ang Li
- Faculty of Materials and Manufacturing, Beijing Key Lab of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing, 100124, P. R. China
| | - Na Lu
- Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission, Key Laboratory of Photosensitive Materials and Devices of Liaoning Province, School of Physics and Materials Engineering, Dalian Minzu University, 18 Liaohe West Road, Dalian, 116600, P. R. China
- Dalian Key Laboratory of Low-Dimensional Semiconductor Optoelectronic Materials and Applications, School of Physics and Materials Engineering, Dalian Minzu University, 18 Liaohe West Road, Dalian, 116600, P. R. China
| | - Wei Lu
- Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission, Key Laboratory of Photosensitive Materials and Devices of Liaoning Province, School of Physics and Materials Engineering, Dalian Minzu University, 18 Liaohe West Road, Dalian, 116600, P. R. China
- Dalian Key Laboratory of Low-Dimensional Semiconductor Optoelectronic Materials and Applications, School of Physics and Materials Engineering, Dalian Minzu University, 18 Liaohe West Road, Dalian, 116600, P. R. China
| | - Yongan Zhu
- Dalian Key Laboratory of Low-Dimensional Semiconductor Optoelectronic Materials and Applications, School of Physics and Materials Engineering, Dalian Minzu University, 18 Liaohe West Road, Dalian, 116600, P. R. China
| | - Zhenyi Zhang
- Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission, Key Laboratory of Photosensitive Materials and Devices of Liaoning Province, School of Physics and Materials Engineering, Dalian Minzu University, 18 Liaohe West Road, Dalian, 116600, P. R. China
- Dalian Key Laboratory of Low-Dimensional Semiconductor Optoelectronic Materials and Applications, School of Physics and Materials Engineering, Dalian Minzu University, 18 Liaohe West Road, Dalian, 116600, P. R. China
| |
Collapse
|
3
|
Arif O, Canal L, Ferrari E, Ferrari C, Lazzarini L, Nasi L, Paghi A, Heun S, Sorba L. Influence of an Overshoot Layer on the Morphological, Structural, Strain, and Transport Properties of InAs Quantum Wells. Nanomaterials (Basel) 2024; 14:592. [PMID: 38607126 PMCID: PMC11013858 DOI: 10.3390/nano14070592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 03/23/2024] [Accepted: 03/25/2024] [Indexed: 04/13/2024]
Abstract
InAs quantum wells (QWs) are promising material systems due to their small effective mass, narrow bandgap, strong spin-orbit coupling, large g-factor, and transparent interface to superconductors. Therefore, they are promising candidates for the implementation of topological superconducting states. Despite this potential, the growth of InAs QWs with high crystal quality and well-controlled morphology remains challenging. Adding an overshoot layer at the end of the metamorphic buffer layer, i.e., a layer with a slightly larger lattice constant than the active region of the device, helps to overcome the residual strain and provides optimally relaxed lattice parameters for the QW. In this work, we systematically investigated the influence of overshoot layer thickness on the morphological, structural, strain, and transport properties of undoped InAs QWs on GaAs(100) substrates. Transmission electron microscopy reveals that the metamorphic buffer layer, which includes the overshoot layer, provides a misfit dislocation-free InAs QW active region. Moreover, the residual strain in the active region is compressive in the sample with a 200 nm-thick overshoot layer but tensile in samples with an overshoot layer thicker than 200 nm, and it saturates to a constant value for overshoot layer thicknesses above 350 nm. We found that electron mobility does not depend on the crystallographic directions. A maximum electron mobility of 6.07 × 105 cm2/Vs at 2.6 K with a carrier concentration of 2.31 × 1011 cm-2 in the sample with a 400 nm-thick overshoot layer has been obtained.
Collapse
Affiliation(s)
- Omer Arif
- NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza S. Silvestro 12, I-56127 Pisa, Italy; (O.A.); (L.C.); (A.P.); (S.H.)
| | - Laura Canal
- NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza S. Silvestro 12, I-56127 Pisa, Italy; (O.A.); (L.C.); (A.P.); (S.H.)
| | - Elena Ferrari
- Istituto dei Materiali per l’Elettronica ed il Magnetismo, Consiglio Nazionale delle Ricerche (IMEM–CNR), Parco Area delle Scienze 37/A, I-43124 Parma, Italy; (E.F.); (C.F.); (L.L.); (L.N.)
| | - Claudio Ferrari
- Istituto dei Materiali per l’Elettronica ed il Magnetismo, Consiglio Nazionale delle Ricerche (IMEM–CNR), Parco Area delle Scienze 37/A, I-43124 Parma, Italy; (E.F.); (C.F.); (L.L.); (L.N.)
| | - Laura Lazzarini
- Istituto dei Materiali per l’Elettronica ed il Magnetismo, Consiglio Nazionale delle Ricerche (IMEM–CNR), Parco Area delle Scienze 37/A, I-43124 Parma, Italy; (E.F.); (C.F.); (L.L.); (L.N.)
| | - Lucia Nasi
- Istituto dei Materiali per l’Elettronica ed il Magnetismo, Consiglio Nazionale delle Ricerche (IMEM–CNR), Parco Area delle Scienze 37/A, I-43124 Parma, Italy; (E.F.); (C.F.); (L.L.); (L.N.)
| | - Alessandro Paghi
- NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza S. Silvestro 12, I-56127 Pisa, Italy; (O.A.); (L.C.); (A.P.); (S.H.)
| | - Stefan Heun
- NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza S. Silvestro 12, I-56127 Pisa, Italy; (O.A.); (L.C.); (A.P.); (S.H.)
| | - Lucia Sorba
- NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza S. Silvestro 12, I-56127 Pisa, Italy; (O.A.); (L.C.); (A.P.); (S.H.)
| |
Collapse
|
4
|
He H, Xing Y, Cui Z, Qin S, Wen Z, Yang D, Xie H, Mei S, Zhang W, Guo R. Regulating Phase Distribution of Dion-Jacobson Perovskite Colloidal Multiple Quantum Wells Toward Highly Stable Deep-Blue Emission. Small 2024; 20:e2305191. [PMID: 37752759 DOI: 10.1002/smll.202305191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 09/13/2023] [Indexed: 09/28/2023]
Abstract
Metal halide perovskite colloidal quantum wells (CQWs) hold great promise for modern photonics and optoelectronics. However, current studies focus on Ruddlesden-Popper (R-P) phase perovskite CQWs that contain bilayers of monovalent long-chain alkylamomoniums between the separated perovskite octahedra layers. The bilayers are packed back-to-back via weak van der Waals interaction, resulting in inferior charge carrier transport and easier decomposition of perovskite. This report first creates a new type of perovskite colloidal multiple QWs (CMQWs) in the form of Dion-Jacobson (D-J) structure by introducing an asymmetric diammonium cation. Furthermore, the phase distribution is optimized by the synergistic effect of valeric acid and zwitterionic lecithin, finally achieving pure deep-blue emission at 435 nm with narrow full width at half maximum. The diammonium layer in D-J perovskite CMQWs features extremely short width of only ≈0.6 nm, thereby contributing to more effective charge carrier transport and higher stability. Through the continuous photoluminescence (PL) measurement and corresponding theoretical calculation, the higher stability of D-J perovskite CMQWs than that of R-P structural CMQWs is confirmed. This work reveals the inherent superior stability of D-J structural CMQWs, which opens a new direction for fabricating stable perovskite optoelectronics.
Collapse
Affiliation(s)
- Haiyang He
- Institute for Electric Light Sources, School of Information Science and Technology, Fudan University, Shanghai, 200433, China
| | - Yifeng Xing
- Institute of Future Lighting, Academy for Engineering and Technology, Fudan University, Shanghai, 200433, China
| | - Zhongjie Cui
- Institute for Electric Light Sources, School of Information Science and Technology, Fudan University, Shanghai, 200433, China
| | - Shuaitao Qin
- Institute for Electric Light Sources, School of Information Science and Technology, Fudan University, Shanghai, 200433, China
| | - Zhuoqi Wen
- Institute of Future Lighting, Academy for Engineering and Technology, Fudan University, Shanghai, 200433, China
| | - Dan Yang
- Institute for Electric Light Sources, School of Information Science and Technology, Fudan University, Shanghai, 200433, China
| | - Haijiao Xie
- Hangzhou Yanqu Information Technology Co., Ltd, Xihu District, Hangzhou City, Zhejiang, 310003, China
| | - Shiliang Mei
- Institute for Electric Light Sources, School of Information Science and Technology, Fudan University, Shanghai, 200433, China
| | - Wanlu Zhang
- Institute for Electric Light Sources, School of Information Science and Technology, Fudan University, Shanghai, 200433, China
| | - Ruiqian Guo
- Institute for Electric Light Sources, School of Information Science and Technology, Fudan University, Shanghai, 200433, China
- Institute of Future Lighting, Academy for Engineering and Technology, Fudan University, Shanghai, 200433, China
- Yiwu Research Institute of Fudan University, Chengbei Road, Yiwu City, Zhejiang, 322000, China
- Zhongshan - Fudan Joint Innovation Center, Zhongshan, 528437, China
| |
Collapse
|
5
|
Zheng DG, Min S, Kim J, Han DP. Growth of Ga 0.70In 0.30N/GaN Quantum-Wells on a ScAlMgO 4 (0001) Substrate with an Ex- Situ Sputtered-AlN Buffer Layer. Materials (Basel) 2023; 17:167. [PMID: 38204021 PMCID: PMC10779881 DOI: 10.3390/ma17010167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/19/2023] [Accepted: 12/21/2023] [Indexed: 01/12/2024]
Abstract
This study attempted to improve the internal quantum efficiency (IQE) of 580 nm emitting Ga0.70In0.30N/GaN quantum-wells (QWs) through the replacement of a conventional c-sapphire substrate and an in-situ low-temperature GaN (LT-GaN) buffer layer with the ScAlMgO4 (0001) (SCAM) substrate and an ex-situ sputtered-AlN (sp-AlN) buffer layer, simultaneously. To this end, we initially tried to optimize the thickness of the sp-AlN buffer layer by investigating the properties/qualities of an undoped-GaN (u-GaN) template layer grown on the SCAM substrate with the sp-AlN buffer layer in terms of surface morphology, crystallographic orientation, and dislocation type/density. The experimental results showed that the crystallinity of the u-GaN layer grown on the SCAM substrate with the 30 nm thick sp-AlN buffer layer [GaN/sp-AlN(30 nm)/SCAM] was superior to that of the conventional u-GaN template layer grown on the c-sapphire substrate with an LT-GaN buffer layer (GaN/LT-GaN/FSS). Notably, the experimental results showed that the structural properties and crystallinity of GaN/sp-AlN(30 nm)/SCAM were considerably different from those of GaN/LT-GaN/FSS. Specifically, the edge-type dislocation density was approximately two orders of magnitude higher than the screw-/mixed-type dislocation density, i.e., the generation of screw-/mixed-type dislocation was suppressed through the replacement, unlike that of the GaN/LT-GaN/FSS. Next, to investigate the effect of replacement on the subsequent QW active layers, 580 nm emitting Ga0.70In0.30N/GaN QWs were grown on the u-GaN template layers. The IQEs of the samples were measured by means of temperature-dependent photoluminescence efficiency, and the results showed that the replacement improved the IQE at 300 K by approximately 1.8 times. We believe that the samples fabricated and described in the present study can provide a greater insight into future research directions for III-nitride light-emitting devices operating in yellow-red spectral regions.
Collapse
Affiliation(s)
- Dong-Guang Zheng
- Department of Electronic and Communication, Hangzhou Dianzi University Information Engineering College, Hangzhou 311305, China;
| | - Sangjin Min
- Department of Photonics and Nanoelectronics, Hanyang University, Ansan 15588, Gyeonggi, Republic of Korea; (S.M.); (J.K.)
| | - Jiwon Kim
- Department of Photonics and Nanoelectronics, Hanyang University, Ansan 15588, Gyeonggi, Republic of Korea; (S.M.); (J.K.)
| | - Dong-Pyo Han
- Department of Display & Semiconductor Engineering, School of Electrical Engineering, Pukyoung National University, Busan 48513, Republic of Korea
| |
Collapse
|
6
|
Khudaiberdiev D, Kvon ZD, Entin MV, Kozlov DA, Mikhailov NN, Ryzhkov M. Mesoscopic Conductance Fluctuations in 2D HgTe Semimetal. Nanomaterials (Basel) 2023; 13:2882. [PMID: 37947727 PMCID: PMC10648201 DOI: 10.3390/nano13212882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 10/28/2023] [Accepted: 10/28/2023] [Indexed: 11/12/2023]
Abstract
Mesoscopic conductance fluctuations were discovered in a weak localization regime of a strongly disordered two-dimensional HgTe-based semimetal. These fluctuations exist in macroscopic samples with characteristic sizes of 100 μm and exhibit anomalous dependences on the gate voltage, magnetic field, and temperature. They are absent in the regime of electron metal (at positive gate voltages) and strongly depend on the level of disorder in the system. All the experimental facts lead us to the conclusion that the origin of the fluctuations is a special collective state in which the current is conducted through the percolation network of electron resistances. We suppose that the network is formed by fluctuation potential whose amplitude is higher than the Fermi level of electrons due to their very low density.
Collapse
Affiliation(s)
- Daniiar Khudaiberdiev
- Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria; (D.K.)
- Rzhanov Institute of Semiconductor Physics, Novosibirsk 630090, Russia
| | - Ze Don Kvon
- Rzhanov Institute of Semiconductor Physics, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk 630090, Russia
| | - Matvey V. Entin
- Rzhanov Institute of Semiconductor Physics, Novosibirsk 630090, Russia
| | - Dmitriy A. Kozlov
- Rzhanov Institute of Semiconductor Physics, Novosibirsk 630090, Russia
- Experimental and Applied Physics, University of Regensburg, D-93040 Regensburg, Germany
| | - Nikolay N. Mikhailov
- Rzhanov Institute of Semiconductor Physics, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk 630090, Russia
| | - Maxim Ryzhkov
- Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria; (D.K.)
- Rzhanov Institute of Semiconductor Physics, Novosibirsk 630090, Russia
| |
Collapse
|
7
|
En-nadir R, Basyooni-M. Kabatas MA, Tihtih M, Belaid W, Ez-zejjari I, Majda EG, El Ghazi H, Sali A, Zorkani I. Enhancing Emission via Radiative Lifetime Manipulation in Ultrathin InGaN/GaN Quantum Wells: The Effects of Simultaneous Electric and Magnetic Fields, Thickness, and Impurity. Nanomaterials (Basel) 2023; 13:2817. [PMID: 37947663 PMCID: PMC10648222 DOI: 10.3390/nano13212817] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 10/20/2023] [Accepted: 10/23/2023] [Indexed: 11/12/2023]
Abstract
Ultra-thin quantum wells, with their unique charge confinement effects, are essential in enhancing the electronic and optical properties crucial for optoelectronic device optimization. This study focuses on theoretical investigations into radiative recombination lifetimes in nanostructures, specifically addressing both intra-subband (ISB: e-e) and band-to-band (BTB: e-hh) transitions within InGaN/GaN quantum wells (QWs). Our research unveils that the radiative lifetimes in ISB and BTB transitions are significantly influenced by external excitation, particularly in thin-layered QWs with strong confinement effects. In the case of ISB transitions (e-e), the recombination lifetimes span a range from 0.1 to 4.7 ns, indicating relatively longer durations. On the other hand, BTB transitions (e-hh) exhibit quicker lifetimes, falling within the range of 0.01 to 1 ns, indicating comparatively faster recombination processes. However, it is crucial to note that the thickness of the quantum well layer exerts a substantial influence on the radiative lifetime, whereas the presence of impurities has a comparatively minor impact on these recombination lifetimes. This research advances our understanding of transition lifetimes in quantum well systems, promising enhancements across optoelectronic applications, including laser diodes and advanced technologies in detection, sensing, and telecommunications.
Collapse
Affiliation(s)
- Redouane En-nadir
- LPS, Department of Physics, Sidi Mohamed Ben Abdullah University, P.O. Box 1796, Atlas Fez 30000, Morocco; (H.E.G.); (A.S.); (I.Z.)
| | - Mohamed A. Basyooni-M. Kabatas
- Department of Precision and Microsystems Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
- Department of Nanotechnology and Advanced Materials, Graduate School of Applied and Natural Science, Selçuk University, Konya 42030, Turkey
| | - Mohammed Tihtih
- Institute of Ceramic and Polymer Engineering, University of Miskolc, 3515 Miskolc, Hungary;
| | - Walid Belaid
- Department of Physics, Faculty of Science, Sélçuk University, Konya 42031, Turkey;
| | - Ilyass Ez-zejjari
- ENSAM, University Hassan-II, Casablanca 20670, Morocco; (I.E.-z.); (E.G.M.)
| | - El Ghmari Majda
- ENSAM, University Hassan-II, Casablanca 20670, Morocco; (I.E.-z.); (E.G.M.)
| | - Haddou El Ghazi
- LPS, Department of Physics, Sidi Mohamed Ben Abdullah University, P.O. Box 1796, Atlas Fez 30000, Morocco; (H.E.G.); (A.S.); (I.Z.)
- ENSAM, University Hassan-II, Casablanca 20670, Morocco; (I.E.-z.); (E.G.M.)
| | - Ahmed Sali
- LPS, Department of Physics, Sidi Mohamed Ben Abdullah University, P.O. Box 1796, Atlas Fez 30000, Morocco; (H.E.G.); (A.S.); (I.Z.)
| | - Izeddine Zorkani
- LPS, Department of Physics, Sidi Mohamed Ben Abdullah University, P.O. Box 1796, Atlas Fez 30000, Morocco; (H.E.G.); (A.S.); (I.Z.)
| |
Collapse
|
8
|
Rodriguez-Osorio KG, Morán-Lázaro JP, Ojeda-Martínez M, Montoya De Los Santos I, Ouarie NE, Feddi EM, Pérez LM, Laroze D, Routray S, Sánchez-Rodríguez FJ, Courel M. Analytical Modeling and Optimization of Cu 2ZnSn(S,Se) 4 Solar Cells with the Use of Quantum Wells under the Radiative Limit. Nanomaterials (Basel) 2023; 13:2058. [PMID: 37513069 PMCID: PMC10384985 DOI: 10.3390/nano13142058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 07/04/2023] [Accepted: 07/07/2023] [Indexed: 07/30/2023]
Abstract
In this work, we present a theoretical study on the use of Cu2ZnSn(S,Se)4 quantum wells in Cu2ZnSnS4 solar cells to enhance device efficiency. The role of different well thickness, number, and S/(S + Se) composition values is evaluated. The physical mechanisms governing the optoelectronic parameters are analyzed. The behavior of solar cells based on Cu2ZnSn(S,Se)4 without quantum wells is also considered for comparison. Cu2ZnSn(S,Se)4 quantum wells with a thickness lower than 50 nm present the formation of discretized eigenstates which play a fundamental role in absorption and recombination processes. Results show that well thickness plays a more important role than well number. We found that the use of wells with thicknesses higher than 20 nm allow for better efficiencies than those obtained for a device without nanostructures. A record efficiency of 37.5% is achieved when 36 wells with a width of 50 nm are used, considering an S/(S + Se) well compositional ratio of 0.25.
Collapse
Affiliation(s)
- Karina G Rodriguez-Osorio
- Centro Universitario de los Valles, Universidad de Guadalajara, Carretera Guadalajara-Ameca Km. 45.5, Ameca C.P. 46600, Jalisco, Mexico
| | - Juan P Morán-Lázaro
- Centro Universitario de los Valles, Universidad de Guadalajara, Carretera Guadalajara-Ameca Km. 45.5, Ameca C.P. 46600, Jalisco, Mexico
| | - Miguel Ojeda-Martínez
- Centro Universitario de los Valles, Universidad de Guadalajara, Carretera Guadalajara-Ameca Km. 45.5, Ameca C.P. 46600, Jalisco, Mexico
| | - Isaac Montoya De Los Santos
- Instituto de Estudios de la Energía, Universidad del Istmo, Santo Domingo Tehuantepec C.P. 70760, Oaxaca, Mexico
| | - Nassima El Ouarie
- Group of Optoelectronic of Semiconductors and Nanomaterials, ENSAM, Mohammed V University in Rabat, Rabat 10100, Morocco
| | - El Mustapha Feddi
- Group of Optoelectronic of Semiconductors and Nanomaterials, ENSAM, Mohammed V University in Rabat, Rabat 10100, Morocco
- Institute of Applied Physics, Mohammed VI Polytechnic University, Lot 660, Hay Moulay Rachid, Ben Guerir 43150, Morocco
| | - Laura M Pérez
- Departamento de Física, FACI, Universidad de Tarapacá, Casilla 7D, Arica 1000000, Chile
| | - David Laroze
- Instituto de Alta Investigación, Universidad de Tarapacá, Casilla 7D, Arica 1000000, Chile
| | - Soumyaranjan Routray
- Department of Electronics and Communication Engineering, SRM Institute of Science and Technology, Chennai 603203, India
| | | | - Maykel Courel
- Centro Universitario de los Valles, Universidad de Guadalajara, Carretera Guadalajara-Ameca Km. 45.5, Ameca C.P. 46600, Jalisco, Mexico
| |
Collapse
|
9
|
Du Y, Tian Q, Wang S, Yang T, Yin L, Zhang H, Cai W, Wu Y, Huang W, Zhang L, Zhao K, Liu SF. Manipulating the Formation of 2D/3D Heterostructure in Stable High-Performance Printable CsPbI 3 Perovskite Solar Cells. Adv Mater 2023; 35:e2206451. [PMID: 36427296 DOI: 10.1002/adma.202206451] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 11/15/2022] [Indexed: 06/16/2023]
Abstract
Manipulating the formation process of the 2D/3D perovskite heterostructure, including its nucleation/growth dynamics and phase transition pathway, plays a critical role in controlling the charge transport between 2D and 3D crystals, and consequently, the scalable fabrication of efficient and stable perovskite solar cells. Herein, the structural evolution and phase transition pathways of the ligand-dependent 2D perovskite atop the 3D surface are revealed using time-resolved X-ray scattering. The results show that the ligand size and shape have a critical influence on the final 2D structure. In particular, ligands with smaller sizes and more reactive sites tend to form the n = 1 phase. Increasing the ligand size and decreasing the reactive sites promote the transformation from 3D to n = 3 and n < 3 phases. These findings are useful for the rational design of the phase distribution in 2D perovskites to balance the charge transport and stability of the perovskite films. Finally, solar cells based on ambient-printed CsPbI3 with n-butylammonium iodide treatment achieve an improved efficiency of 20.33%, which is the highest reported value for printed inorganic perovskite solar cells.
Collapse
Affiliation(s)
- Yachao Du
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, P. R. China
| | - Qingwen Tian
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, P. R. China
| | - Shiqiang Wang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, P. R. China
| | - Tinghuan Yang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, P. R. China
| | - Lei Yin
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, P. R. China
| | - Hao Zhang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, P. R. China
| | - Weilun Cai
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, P. R. China
| | - Yin Wu
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, P. R. China
| | - Wenliang Huang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, P. R. China
| | - Lu Zhang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, P. R. China
| | - Kui Zhao
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, P. R. China
| | - Shengzhong Frank Liu
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, P. R. China
- Dalian National Laboratory for Clean Energy, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P. R. China
| |
Collapse
|
10
|
Tereshchenko OE, Golyashov VA, Rusetsky VS, Kustov DA, Mironov AV, Demin AY. Vacuum Spin LED: First Step towards Vacuum Semiconductor Spintronics. Nanomaterials (Basel) 2023; 13:422. [PMID: 36770383 PMCID: PMC9919810 DOI: 10.3390/nano13030422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 01/14/2023] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
Improving the efficiency of spin generation, injection, and detection remains a key challenge for semiconductor spintronics. Electrical injection and optical orientation are two methods of creating spin polarization in semiconductors, which traditionally require specially tailored p-n junctions, tunnel or Schottky barriers. Alternatively, we introduce here a novel concept for spin-polarized electron emission/injection combining the optocoupler principle based on vacuum spin-polarized light-emitting diode (spin VLED) making it possible to measure the free electron beam polarization injected into the III-V heterostructure with quantum wells (QWs) based on the detection of polarized cathodoluminescence (CL). To study the spin-dependent emission/injection, we developed spin VLEDs, which consist of a compact proximity-focused vacuum tube with a spin-polarized electron source (p-GaAs(Cs,O) or Na2KSb) and the spin detector (III-V heterostructure), both activated to a negative electron affinity (NEA) state. The coupling between the photon helicity and the spin angular momentum of the electrons in the photoemission and injection/detection processes is realized without using either magnetic material or a magnetic field. Spin-current detection efficiency in spin VLED is found to be 27% at room temperature. The created vacuum spin LED paves the way for optical generation and spin manipulation in the developing vacuum semiconductor spintronics.
Collapse
Affiliation(s)
- Oleg E. Tereshchenko
- Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia
- Synchrotron Radiation Facility SKIF, Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences, Kol’tsovo 630559, Russia
| | - Vladimir A. Golyashov
- Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia
- Synchrotron Radiation Facility SKIF, Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences, Kol’tsovo 630559, Russia
| | - Vadim S. Rusetsky
- Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia
- CJSC “Ekran FEP”, Novosibirsk 630060, Russia
| | - Danil A. Kustov
- Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | | | | |
Collapse
|
11
|
Yu X, Dai Y, Lu Y, Liu C, Yan Y, Shen R, Yang Z, Feng L, Sun L, Liu Y, Lin S. High Efficient Solar Cell Based on Heterostructure Constructed by Graphene and GaAs Quantum Wells. Adv Sci (Weinh) 2023; 10:e2204058. [PMID: 36394152 PMCID: PMC9839879 DOI: 10.1002/advs.202204058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 10/10/2022] [Indexed: 06/16/2023]
Abstract
Despite the fascinating optoelectronic properties of graphene, the power conversion efficiency (PCE) of graphene based solar cells remains to be lifted up. Herein, it is experimentally shown that the graphene/quantum wells/GaAs heterostructure solar cell can reach a PCE of 20.2% and an open-circuit voltage (Voc ) as high as 1.16 V at 90 K. The high efficiency is a result of carrier multiplication (CM) effect of graphene in the graphene/GaAs heterostructure. Especially, the external quantum efficiency (EQE) in the ultraviolet wavelength can be improved up to 72.2% based on the heterostructure constructed by graphene/In0.15 Ga0.85 As/GaAs0.75 P0.25 quantum wells/GaAs. The EQE increases as the light wavelength decreases, which indicates more carriers can be effectively excited by the higher energy photons through CM effect. Owing to these physical characters, the graphene/GaAs heterostructure solar cell will provide a possible way to exceed Shockley-Queisser (S-Q) limit.
Collapse
Affiliation(s)
- Xutao Yu
- College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Yue Dai
- College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Yanghua Lu
- College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Chang Liu
- College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Yanfei Yan
- College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Runjiang Shen
- College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Zunshan Yang
- College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Lixuan Feng
- College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Lijie Sun
- State Key Laboratory of Space Power Technology, Shanghai Institute of Space Power Sources, Shanghai, 200245, P. R. China
| | - Yong Liu
- State Key Laboratory of Space Power Technology, Shanghai Institute of Space Power Sources, Shanghai, 200245, P. R. China
| | - Shisheng Lin
- College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
- State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou, 310027, P. R. China
| |
Collapse
|
12
|
Petersen N, Girard M, Riedinger A, Valsson O. The Crucial Role of Solvation Forces in the Steric Stabilization of Nanoplatelets. Nano Lett 2022; 22:9847-9853. [PMID: 36493312 PMCID: PMC9801426 DOI: 10.1021/acs.nanolett.2c02848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 12/02/2022] [Indexed: 06/17/2023]
Abstract
The steric stability of inorganic colloidal particles in an apolar solvent is usually described in terms of the balance between three contributions: the van der Waals attraction, the free energy of mixing, and the ligand compression. However, in the case of nanoparticles, the discrete nature of the ligand shell and the solvent has to be taken into account. Cadmium selenide nanoplatelets are a special case. They combine a weak van der Waals attraction and a large facet to particle size ratio. We use coarse grained molecular dynamics simulations of nanoplatelets in octane to demonstrate that solvation forces are strong enough to induce the formation of nanoplatelet stacks and by that have a crucial impact on the steric stability. In particular, we demonstrate that for sufficiently large nanoplatelets, solvation forces are proportional to the interacting facet area, and their strength is intrinsically tied to the softness of the ligand shell.
Collapse
Affiliation(s)
- Nanning Petersen
- Max
Planck Institute for Polymer Research, Mainz D-55128, Germany
| | - Martin Girard
- Max
Planck Institute for Polymer Research, Mainz D-55128, Germany
| | | | - Omar Valsson
- Max
Planck Institute for Polymer Research, Mainz D-55128, Germany
- Department
of Chemistry, University of North Texas, Denton, Texas 76201, United States
| |
Collapse
|
13
|
Udai A, Ganguly S, Bhattacharya P, Saha D. Real-time observation of delayed excited-state dynamics in InGaN/GaN quantum-wells by femtosecond transient absorption spectroscopy. Nanotechnology 2022; 33:475202. [PMID: 35977452 DOI: 10.1088/1361-6528/ac8a50] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Accepted: 08/17/2022] [Indexed: 06/15/2023]
Abstract
This work employs femtosecond transient absorption spectroscopy to investigate the ultrafast carrier dynamics of bound states in In0.14Ga0.86N/GaN quantum wells. The ground state (GS) dynamics usually dominate these characteristics, appearing as a prominent peak in the absorption spectra. It is observed that the excited state also contributes to the overall dynamics, with its signature showing up later. The contributions of both the ground and excited states in the absorption spectra and time-resolved dynamics are decoupled in this work. The carrier density in the GS first increases and then decays with time. The carriers populate the excited state only at a delayed time. The dynamics are studied considering the Quantum-Confined Stark Effect-induced wavelength shift in the absorption. The relevant microscopic optoelectronic processes are understood phenomenologically, and their time constants are extracted. An accurate study of these dynamics provides fundamentally essential insights into the time-resolved dynamics in quantum-confined heterostructures and can facilitate the development of efficient light sources using GaN heterostructures.
Collapse
Affiliation(s)
- Ankit Udai
- Applied Quantum Mechanics Laboratory, Indian Institute of Technology; Bombay, Powai, Mumbai-400076, India
| | - Swaroop Ganguly
- Applied Quantum Mechanics Laboratory, Indian Institute of Technology; Bombay, Powai, Mumbai-400076, India
| | - Pallab Bhattacharya
- Solid-State Electronics Laboratory, Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, 48109-2122, United States of America
| | - Dipankar Saha
- Applied Quantum Mechanics Laboratory, Indian Institute of Technology; Bombay, Powai, Mumbai-400076, India
| |
Collapse
|
14
|
Abstract
We show that a Bose-Einstein condensate consisting of dark excitons forms in GaAs coupled quantum wells at low temperatures. We find that the condensate extends over hundreds of micrometers, well beyond the optical excitation region, and is limited only by the boundaries of the mesa. We show that the condensate density is determined by spin-flipping collisions among the excitons, which convert dark excitons into bright ones. The suppression of this process at low temperature yields a density buildup, manifested as a temperature-dependent blueshift of the exciton emission line. Measurements under an in-plane magnetic field allow us to preferentially modify the bright exciton density and determine their role in the system dynamics. We find that their interaction with the condensate leads to its depletion. We present a simple rate-equations model, which well reproduces the observed temperature, power, and magnetic-field dependence of the exciton density.
Collapse
|
15
|
Han DP, Iwaya M, Takeuchi T, Kamiyama S. Pre-trimethylindium Flow Treatment of GaInN/GaN Quantum Wells to Suppress Surface Defect Incorporation and Improve Efficiency. ACS Appl Mater Interfaces 2022; 14:26264-26270. [PMID: 35609181 DOI: 10.1021/acsami.2c05585] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
This study aims to improve the emission efficiency of GaInN-based green light-emitting devices (LEDs) using the pre-trimethylindium (TMIn) flow treatment of a quantum well (QW) since we hypothesize that the pre-TMIn flow treatment is able to suppress the incorporation of surface defects (SDs) from the n-type GaN surface into the QWs. For this purpose, first, we investigate the effect of TMIn flow treatment on the SDs in n-type GaN samples by measuring time-resolved photoluminescence. The result of the investigation shows that the TMIn flow treatment effectively deactivated and/or neutralized the SDs from acting as the nonradiative recombination centers. Next, we prepare and investigate the GaInN-based green LEDs employing five pairs of multiple quantum wells (MQWs), in which the number of pre-TMIn treated QWs varies from zero to five. Through the analysis of prepared samples, we demonstrate that the pre-TMIn flow treatment of QWs works effectively in suppressing the SD incorporation into the MQWs, thereby improving the emission intensity.
Collapse
Affiliation(s)
- Dong-Pyo Han
- Faculty of Science and Technology, Meijo University, Nagoya 468-8502, Japan
| | - Motoaki Iwaya
- Faculty of Science and Technology, Meijo University, Nagoya 468-8502, Japan
| | - Tetsuya Takeuchi
- Faculty of Science and Technology, Meijo University, Nagoya 468-8502, Japan
| | - Satoshi Kamiyama
- Faculty of Science and Technology, Meijo University, Nagoya 468-8502, Japan
| |
Collapse
|
16
|
Gudina SV, Neverov VN, Popov MR, Turutkin KV, Podgornykh SM, Shelushinina NG, Yakunin MV, Mikhailov NN, Dvoretsky SA. Rashba Spin Splitting in HgCdTe Quantum Wells with Inverted and Normal Band Structures. Nanomaterials (Basel) 2022; 12:1238. [PMID: 35407355 DOI: 10.3390/nano12071238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 03/23/2022] [Accepted: 03/31/2022] [Indexed: 02/01/2023]
Abstract
In quantum wells (QWs) formed in HgCdTe/CdHgTe heterosystems with a variable composition of Cd(Hg), Shubnikov-de-Haas (SdH) oscillations are investigated to characterize the Rashba-type spin-orbit coupling in QWs with both a normal and inverted band structure. Several methods of extracting the Rashba spin-splitting at zero magnetic field and their magnetic field dependences from the beatings of SdH oscillations are used for greater reliability. The large and similar Rashba splitting (25–27 meV) is found for different kinds of spectrum, explained by a significant fraction of the p-type wave functions, in both the E1 subband of the sample with a normal spectrum and the H1 subband for the sample with an inverted one.
Collapse
|
17
|
Titze VM, Caixeiro S, Di Falco A, Schubert M, Gather MC. Red-Shifted Excitation and Two-Photon Pumping of Biointegrated GaInP/AlGaInP Quantum Well Microlasers. ACS Photonics 2022; 9:952-960. [PMID: 35434182 PMCID: PMC9007562 DOI: 10.1021/acsphotonics.1c01807] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Indexed: 06/01/2023]
Abstract
Biointegrated intracellular microlasers have emerged as an attractive and versatile tool in biophotonics. Different inorganic semiconductor materials have been used for the fabrication of such biocompatible microlasers but often operate at visible wavelengths ill-suited for imaging through tissue. Here, we report on whispering gallery mode microdisk lasers made from a range of GaInP/AlGaInP multi-quantum well structures with compositions tailored to red-shifted excitation and emission. The selected semiconductor alloys show minimal toxicity and allow the fabrication of lasers with stable single-mode emission in the NIR (675-720 nm) and sub-pJ thresholds. The microlasers operate in the first therapeutic window under direct excitation by a conventional diode laser and can also be pumped in the second therapeutic window using two-photon excitation at pulse energies compatible with standard multiphoton microscopy. Stable performance is observed under cell culturing conditions for 5 days without any device encapsulation. With their bio-optimized spectral characteristics, low lasing threshold, and compatibility with two-photon pumping, AlGaInP-based microlasers are ideally suited for novel cell tagging and in vivo sensing applications.
Collapse
Affiliation(s)
- Vera M. Titze
- SUPA,
School of Physics and Astronomy, University
of St Andrews, North Haugh, St Andrews KY16 9SS, United Kingdom
| | - Soraya Caixeiro
- SUPA,
School of Physics and Astronomy, University
of St Andrews, North Haugh, St Andrews KY16 9SS, United Kingdom
| | - Andrea Di Falco
- SUPA,
School of Physics and Astronomy, University
of St Andrews, North Haugh, St Andrews KY16 9SS, United Kingdom
| | - Marcel Schubert
- SUPA,
School of Physics and Astronomy, University
of St Andrews, North Haugh, St Andrews KY16 9SS, United Kingdom
- Humboldt
Centre for Nano- and Biophotonics, Institute of Physical Chemistry, University of Cologne, Greinstr. 4-6, D-50939 Cologne, Germany
| | - Malte C. Gather
- SUPA,
School of Physics and Astronomy, University
of St Andrews, North Haugh, St Andrews KY16 9SS, United Kingdom
- Humboldt
Centre for Nano- and Biophotonics, Institute of Physical Chemistry, University of Cologne, Greinstr. 4-6, D-50939 Cologne, Germany
| |
Collapse
|
18
|
Kovalev VM, Boev MV, Kibis OV. All-optical control of excitons in semiconductor quantum wells. J Phys Condens Matter 2022; 34:205301. [PMID: 35203067 DOI: 10.1088/1361-648x/ac5864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 02/24/2022] [Indexed: 06/14/2023]
Abstract
Applying the Floquet theory, we developed the method to control excitonic properties of semiconductor quantum wells (QWs) by a high-frequency electromagnetic field. It is demonstrated, particularly, that the field induces the blue shift of exciton emission from the QWs and narrows width of the corresponding spectral line. As a consequence, the field strongly modifies optical properties of the QWs and, therefore, can be used to tune characteristics of the optoelectronic devices based on them.
Collapse
Affiliation(s)
- V M Kovalev
- Department of Applied and Theoretical Physics, Novosibirsk State Technical University, Karl Marx Avenue 20, Novosibirsk 630073, Russia
| | - M V Boev
- Department of Applied and Theoretical Physics, Novosibirsk State Technical University, Karl Marx Avenue 20, Novosibirsk 630073, Russia
| | - O V Kibis
- Department of Applied and Theoretical Physics, Novosibirsk State Technical University, Karl Marx Avenue 20, Novosibirsk 630073, Russia
| |
Collapse
|
19
|
Sohr P, Wei D, Wang Z, Law S. Strong Coupling in Semiconductor Hyperbolic Metamaterials. Nano Lett 2021; 21:9951-9957. [PMID: 34787424 DOI: 10.1021/acs.nanolett.1c03290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Semiconductor-based layered hyperbolic metamaterials (HMMs) house high-wavevector volume plasmon polariton (VPP) modes in the infrared spectral range. VPP modes have successfully been exploited in the weak-coupling regime through the enhanced Purcell effect. In this paper, we experimentally demonstrate strong coupling between the VPP modes in a semiconductor HMM and the intersubband transition of epitaxially embedded quantum wells. We observe clear anticrossings in the dispersion curves for the zeroth-, first-, second-, and third-order VPP modes, resulting in upper and lower polariton branches for each mode. This demonstration sets the stage for the creation of novel infrared optoelectronic structures combining HMMs with embedded epitaxial emitter or detector structures.
Collapse
Affiliation(s)
- Patrick Sohr
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19702, United States
| | - Dongxia Wei
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19702, United States
| | - Zhengtianye Wang
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19702, United States
| | - Stephanie Law
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19702, United States
| |
Collapse
|
20
|
Helmreich R, Classen A, Fauster T. Negative electron affinity opens quantum well in MgO layers on Ag(100). J Phys Condens Matter 2021; 34:045001. [PMID: 34670197 DOI: 10.1088/1361-648x/ac316c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 10/20/2021] [Indexed: 06/13/2023]
Abstract
Epitaxial MgO films on Ag(100) were studied by photoelectron spectroscopy. From the low-energy part of the spectra we obtain a negative electron affinity of about -0.9 eV. Even though electrons in the lowest conduction band are not confined by a potential barrier at the surface, quantum-well resonances are observed. The dispersion of the conduction band is determined in good agreement with theoretical calculations. Aspects of observing image-potential states predicted by theory on MgO films are discussed.
Collapse
Affiliation(s)
- Rebecca Helmreich
- Lehrstuhl für Festkörperphysik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstraße 7, 91058 Erlangen, Germany
| | - Andrej Classen
- Lehrstuhl für Festkörperphysik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstraße 7, 91058 Erlangen, Germany
| | - Thomas Fauster
- Lehrstuhl für Festkörperphysik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstraße 7, 91058 Erlangen, Germany
| |
Collapse
|
21
|
Iorsh IV, Kibis OV. Optically induced Kondo effect in semiconductor quantum wells. J Phys Condens Matter 2021; 33:495302. [PMID: 34547723 DOI: 10.1088/1361-648x/ac28c2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 09/21/2021] [Indexed: 06/13/2023]
Abstract
It is demonstrated theoretically that the circularly polarized irradiation of two-dimensional electron systems can induce the localized electron states which antiferromagnetically interact with conduction electrons, resulting in the Kondo effect. Conditions of experimental observation of the effect are discussed for semiconductor quantum wells.
Collapse
Affiliation(s)
- I V Iorsh
- Department of Physics and Engineering, ITMO University, Saint-Petersburg, 197101, Russia
- Department of Applied and Theoretical Physics, Novosibirsk State Technical University, Karl Marx Avenue 20, Novosibirsk 630073, Russia
| | - O V Kibis
- Department of Applied and Theoretical Physics, Novosibirsk State Technical University, Karl Marx Avenue 20, Novosibirsk 630073, Russia
| |
Collapse
|
22
|
Iurov A, Huang D, Gumbs G, Fekete P, Gao F. Defect capturing and charging dynamics and their effects on magneto-transport of electrons in quantum wells. J Phys Condens Matter 2021; 33:395304. [PMID: 34233302 DOI: 10.1088/1361-648x/ac1239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 07/07/2021] [Indexed: 06/13/2023]
Abstract
The calculated defect corrections to the polarization and dielectric functions for Bloch electrons in quantum wells are presented. These results were employed to derive the first two moment equations from the Boltzmann transport theory and then applied to explore the role played by defects on the magneto-transport of Bloch electrons. Additionally, we have derived analytically the inverse momentum-relaxation time and mobility tensor for Bloch electrons by making use of the screened defect-corrected polarization function. Based on quantum-statistical theory, we have investigated the defect capture and charging dynamics by employing a parameterized physics-based model for defects to obtain defect wave functions. Both capture and relaxation rates, as well as the density for captured Bloch electrons, were calculated self-consistently as functions of temperature, doping density and chosen defect parameters. By applying the energy-balance equation, the number of occupied energy levels and the chemical potential of defects were determined, with which the transition rate for defect capturing was obtained. By applying these results, the defect energy-relaxation, capture and escape rates, and Bloch-electron chemical potential were calculated self-consistently for a non-canonical subsystem of Bloch electrons. At the same time, the energy- and momentum-relaxation rates of Bloch electrons, as well as the current suppression factor, were also investigated quantitatively. By combining all these results, the temperature dependence of the Hall and longitudinal mobilities was presented for Bloch electrons in either single- or multi-quantum wells.
Collapse
Affiliation(s)
- Andrii Iurov
- Department of Physics and Computer Science, Medgar Evers College of the City University of New York, Brooklyn, NY 11225, United States of America
| | - Danhong Huang
- Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, NM 87117, United States of America
| | - Godfrey Gumbs
- Department of Physics and Astronomy, Hunter College of the City University of New York, 695 Park Avenue, New York, NY 10065, United States of America
| | - Paula Fekete
- Department of Physics and Nuclear Engineering, US Military Academy at West Point, West Point, New York 10996, United States of America
| | - Fei Gao
- Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109, United States of America
| |
Collapse
|
23
|
Weatherley TFK, Liu W, Osokin V, Alexander DTL, Taylor RA, Carlin JF, Butté R, Grandjean N. Imaging Nonradiative Point Defects Buried in Quantum Wells Using Cathodoluminescence. Nano Lett 2021; 21:5217-5224. [PMID: 34086468 DOI: 10.1021/acs.nanolett.1c01295] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Crystallographic point defects (PDs) can dramatically decrease the efficiency of optoelectronic semiconductor devices, many of which are based on quantum well (QW) heterostructures. However, spatially resolving individual nonradiative PDs buried in such QWs has so far not been demonstrated. Here, using high-resolution cathodoluminescence (CL) and a specific sample design, we spatially resolve, image, and analyze nonradiative PDs in InGaN/GaN QWs at the nanoscale. We identify two different types of PDs by their contrasting behavior with temperature and measure their densities from 1014 cm-3 to as high as 1016 cm-3. Our CL images clearly illustrate the interplay between PDs and carrier dynamics in the well: increasing PD concentration severely limits carrier diffusion lengths, while a higher carrier density suppresses the nonradiative behavior of PDs. The results in this study are readily interpreted directly from CL images and represent a significant advancement in nanoscale PD analysis.
Collapse
Affiliation(s)
- Thomas F K Weatherley
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Wei Liu
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Vitaly Osokin
- Department of Physics, The Clarendon Laboratory, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - Duncan T L Alexander
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Robert A Taylor
- Department of Physics, The Clarendon Laboratory, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - Jean-François Carlin
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Raphaël Butté
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Nicolas Grandjean
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| |
Collapse
|
24
|
Dub M, Sai P, Sakowicz M, Janicki L, But DB, Prystawko P, Cywiński G, Knap W, Rumyantsev S. Double-Quantum-Well AlGaN/GaN Field Effect Transistors with Top and Back Gates: Electrical and Noise Characteristics. Micromachines (Basel) 2021; 12:721. [PMID: 34205287 DOI: 10.3390/mi12060721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/14/2021] [Accepted: 06/16/2021] [Indexed: 11/26/2022]
Abstract
AlGaN/GaN fin-shaped and large-area grating gate transistors with two layers of two-dimensional electron gas and a back gate were fabricated and studied experimentally. The back gate allowed reducing the subthreshold leakage current, improving the subthreshold slope and adjusting the threshold voltage. At a certain back gate voltage, transistors operated as normally-off devices. Grating gate transistors with a high gate area demonstrated little subthreshold leakage current, which could be further reduced by the back gate. The low frequency noise measurements indicated identical noise properties and the same trap density responsible for noise when the transistors were controlled by either top or back gates. This result was explained by the tunneling of electrons to the traps in AlGaN as the main noise mechanism. The trap density extracted from the noise measurements was similar or less than that reported in the majority of publications on regular AlGaN/GaN transistors.
Collapse
|
25
|
Solà-Garcia M, Mauser KW, Liebtrau M, Coenen T, Christiansen S, Meuret S, Polman A. Photon Statistics of Incoherent Cathodoluminescence with Continuous and Pulsed Electron Beams. ACS Photonics 2021; 8:916-925. [PMID: 33763505 PMCID: PMC7976602 DOI: 10.1021/acsphotonics.0c01939] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Indexed: 06/12/2023]
Abstract
Photon bunching in incoherent cathodoluminescence (CL) spectroscopy originates from the fact that a single high-energy electron can generate multiple photons when interacting with a material, thus, revealing key properties of electron-matter excitation. Contrary to previous works based on Monte Carlo modeling, here we present a fully analytical model describing the amplitude and shape of the second order autocorrelation function (g (2)(τ)) for continuous and pulsed electron beams. Moreover, we extend the analysis of photon bunching to ultrashort electron pulses, in which up to 500 electrons per pulse excite the sample within a few picoseconds. We obtain a simple equation relating the bunching strength (g (2)(0)) to the electron beam current, emitter decay lifetime, pulse duration, in the case of pulsed electron beams, and electron excitation efficiency (γ), defined as the probability that an electron creates at least one interaction with the emitter. The analytical model shows good agreement with the experimental data obtained on InGaN/GaN quantum wells using continuous, ns-pulsed (using beam blanker) and ultrashort ps-pulsed (using photoemission) electron beams. We extract excitation efficiencies of 0.13 and 0.05 for 10 and 8 keV electron beams, respectively, and we observe that nonlinear effects play no compelling role, even after excitation with ultrashort and dense electron cascades in the quantum wells.
Collapse
Affiliation(s)
- Magdalena Solà-Garcia
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Kelly W. Mauser
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Matthias Liebtrau
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Toon Coenen
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
- Delmic
BV, Kanaalweg 4, 2628 EB, Delft, The Netherlands
| | - Silke Christiansen
- Fraunhofer
Institute for Ceramic Technologies and Systems IKTS, Äußere Nürnberger Strasse 62, 91301 Forchheim, Germany
| | - Sophie Meuret
- CEMES-CNRS, 29 Rue Jeanne Marvig, 31055 Toulouse, France
| | - Albert Polman
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| |
Collapse
|
26
|
Budkin GV, Makhov IS, Firsov DA. The drag of photons by electric current in quantum wells. J Phys Condens Matter 2021; 33:165301. [PMID: 33498037 DOI: 10.1088/1361-648x/abdff7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 01/26/2021] [Indexed: 06/12/2023]
Abstract
The flow of electric current in quantum well breaks the space inversion symmetry, which leads to the dependence of the radiation transmission on the relative orientation of current and photon wave vector, this phenomenon can be named current drag of photons. We have developed a microscopic theory of such an effect for intersubband transitions in quantum wells taking into account both depolarization and exchange-correlation effects. It is shown that the effect of the current drag of photons originates from the asymmetry of intersubband optical transitions due to the redistribution of electrons in momentum space. We show that the presence of dc electric current leads to the shift of intersubband resonance position and affects both transmission coefficient and absorbance in quantum wells.
Collapse
Affiliation(s)
- G V Budkin
- Ioffe Institute, 194021 St. Petersburg, Russia
| | - I S Makhov
- Peter the Great St. Petersburg Polytechnic University, 195251, St. Petersburg, Russia
| | - D A Firsov
- Peter the Great St. Petersburg Polytechnic University, 195251, St. Petersburg, Russia
| |
Collapse
|
27
|
Vasilchenko AA. Stability of electron-hole liquid in quantum wells. J Phys Condens Matter 2021; 33:145502. [PMID: 33455955 DOI: 10.1088/1361-648x/abdc90] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 01/15/2021] [Indexed: 06/12/2023]
Abstract
Density functional theory is used to calculate the energy of electron-hole liquid and the equilibrium density of electron-hole pairs in quantum wells. Nonlinear Kohn-Sham equations for electrons and holes are solved numerically. The influence of the depth and width of the quantum well, the ratio of the hole and electron masses, and the spin splitting of the hole band on the properties of electron-hole liquid is studied. The critical temperature of electron-hole liquid in quantum wells is estimated. Good agreement between the calculations and experimental results is obtained.
Collapse
Affiliation(s)
- A A Vasilchenko
- Kuban State University, 350040 Krasnodar, Russia
- National Research Tomsk State University, 634050 Tomsk, Russia
| |
Collapse
|
28
|
Shamakhov V, Nikolaev D, Slipchenko S, Fomin E, Smirnov A, Eliseyev I, Pikhtin N, Kop`ev P. Surface Nanostructuring during Selective Area Epitaxy of Heterostructures with InGaAs QWs in the Ultra-Wide Windows. Nanomaterials (Basel) 2020; 11:nano11010011. [PMID: 33374632 PMCID: PMC7822437 DOI: 10.3390/nano11010011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/16/2020] [Accepted: 12/21/2020] [Indexed: 11/16/2022]
Abstract
Selective area epitaxy (SAE) is widely used in photonic integrated circuits, but there is little information on the use of this technique for the growth of heterostructures in ultra-wide windows. Samples of heterostructures with InGaAs quantum wells (QWs) on GaAs (100) substrates with a pattern of alternating stripes (100-μm-wide SiO2 mask/100-μm-wide window) were grown using metalorganic chemical vapour deposition (MOCVD). It was found that due to a local change in the growth rate of InGaAs QW in the window, the photoluminescence (PL) spectra measured from the edge to the center of the window exhibited maximum blueshifts of 14 and 19 meV at temperatures of 80 K and 300 K, respectively. Using atomic force microscopy, we have demonstrated that the surface morphologies of structures grown using standard epitaxy or SAE under identical MOCVD growth conditions correspond to a step flow growth with a step height of ~1.5 ML or a step bunching growth mode, respectively. In the structures grown with the use of SAE, a strong variation in the surface morphology in an ultra-wide window from its center to the edge was revealed, which is explained by a change in the local misorientation of the layer due to a local change in the growth rate over the width of the window.
Collapse
Affiliation(s)
- Viktor Shamakhov
- Ioffe Institute, 26 Politekhnicheskaya, St Petersburg 194021, Russia; (D.N.); (S.S.); (A.S.); (I.E.); (N.P.); (P.K.)
- Correspondence:
| | - Dmitriy Nikolaev
- Ioffe Institute, 26 Politekhnicheskaya, St Petersburg 194021, Russia; (D.N.); (S.S.); (A.S.); (I.E.); (N.P.); (P.K.)
| | - Sergey Slipchenko
- Ioffe Institute, 26 Politekhnicheskaya, St Petersburg 194021, Russia; (D.N.); (S.S.); (A.S.); (I.E.); (N.P.); (P.K.)
| | - Evgenii Fomin
- Elfolum Ltd., 26 Politekhnicheskaya, St Petersburg 194021, Russia;
| | - Alexander Smirnov
- Ioffe Institute, 26 Politekhnicheskaya, St Petersburg 194021, Russia; (D.N.); (S.S.); (A.S.); (I.E.); (N.P.); (P.K.)
| | - Ilya Eliseyev
- Ioffe Institute, 26 Politekhnicheskaya, St Petersburg 194021, Russia; (D.N.); (S.S.); (A.S.); (I.E.); (N.P.); (P.K.)
| | - Nikita Pikhtin
- Ioffe Institute, 26 Politekhnicheskaya, St Petersburg 194021, Russia; (D.N.); (S.S.); (A.S.); (I.E.); (N.P.); (P.K.)
| | - Peter Kop`ev
- Ioffe Institute, 26 Politekhnicheskaya, St Petersburg 194021, Russia; (D.N.); (S.S.); (A.S.); (I.E.); (N.P.); (P.K.)
| |
Collapse
|
29
|
Amerling E, Baniya S, Lafalce E, Blair S, Vardeny ZV, Whittaker-Brooks L. Quantifying Exciton Heterogeneities in Mixed-Phase Organometal Halide Multiple Quantum Wells via Stark Spectroscopy Studies. ACS Appl Mater Interfaces 2020; 12:52538-52548. [PMID: 33179501 DOI: 10.1021/acsami.0c13564] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Solution-processable two-dimensional (2D) organic-inorganic hybrid perovskite (OIHP) quantum wells naturally self-assemble through weak van der Waals forces. In this study, we investigate the structural and optoelectronic properties of 2D-layered butylammonium (C4H9NH3+, BA+) methylammonium (CH3NH3+, MA) lead iodide, (BA)2(MA)n-1PbnI3n+1 quantum wells with varying n from 1 to 4. Through conventional structural characterization, (BA)2(MA)n-1PbnI3n+1 thin films showcase high-quality phase (n) purity. However, while investigating the optoelectronic properties, it is clear that these van der Waals heterostructures consist of multiple quantum well thicknesses coexisting within a single thin film. We utilized electroabsorption spectroscopy and Liptay theory to develop an analytical tool capable of deconvoluting the excitonic features that arise from different quantum well thicknesses (n) in (BA)2(MA)n-1PbnI3n+1 thin films. To obtain a quantitative assessment of exciton heterogeneities within a thin film comprising multiple quantum well structures, exciton resonances quantified by absorption spectroscopy were modeled as Gaussian features to yield various theory-generated electroabsorption spectra, which were then fit to our experimental electroabsorption features. In addition to identifying the quantum well heterostructures present within a thin film, this novel analytical tool provides powerful insights into the exact exciton composition and can be utilized to analyze the optoelectronic properties of many other mixed-phase quantum well heterostructures beyond those formed by OIHPs. Our findings may help in designing more efficient and reproducible light-emitting diodes based on 2D mixed-phase metal-organic multiple quantum wells.
Collapse
Affiliation(s)
- Eric Amerling
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Sangita Baniya
- Department of Physics, University of Utah, Salt Lake City, Utah 84112, United States
| | - Evan Lafalce
- Department of Physics, University of Utah, Salt Lake City, Utah 84112, United States
| | - Steve Blair
- Department of Physics, University of Utah, Salt Lake City, Utah 84112, United States
- Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah 84112, United States
| | - Zeev Valy Vardeny
- Department of Physics, University of Utah, Salt Lake City, Utah 84112, United States
| | | |
Collapse
|
30
|
Sorokin SV, Avdienko PS, Sedova IV, Kirilenko DA, Davydov VY, Komkov OS, Firsov DD, Ivanov SV. Molecular Beam Epitaxy of Layered Group III Metal Chalcogenides on GaAs(001) Substrates. Materials (Basel) 2020; 13:E3447. [PMID: 32764315 DOI: 10.3390/ma13163447] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/27/2020] [Accepted: 07/30/2020] [Indexed: 11/17/2022]
Abstract
Development of molecular beam epitaxy (MBE) of two-dimensional (2D) layered materials is an inevitable step in realizing novel devices based on 2D materials and heterostructures. However, due to existence of numerous polytypes and occurrence of additional phases, the synthesis of 2D films remains a difficult task. This paper reports on MBE growth of GaSe, InSe, and GaTe layers and related heterostructures on GaAs(001) substrates by using a Se valve cracking cell and group III metal effusion cells. The sophisticated self-consistent analysis of X-ray diffraction, transmission electron microscopy, and Raman spectroscopy data was used to establish the correlation between growth conditions, formed polytypes and additional phases, surface morphology and crystalline structure of the III–VI 2D layers. The photoluminescence and Raman spectra of the grown films are discussed in detail to confirm or correct the structural findings. The requirement of a high growth temperature for the fabrication of optically active 2D layers was confirmed for all materials. However, this also facilitated the strong diffusion of group III metals in III–VI and III–VI/II–VI heterostructures. In particular, the strong In diffusion into the underlying ZnSe layers was observed in ZnSe/InSe/ZnSe quantum well structures, and the Ga diffusion into the top InSe layer grown at ~450 °C was confirmed by the Raman data in the InSe/GaSe heterostructures. The results on fabrication of the GaSe/GaTe quantum well structures are presented as well, although the choice of optimum growth temperatures to make them optically active is still a challenge.
Collapse
|
31
|
Yu Y, Wang H, Xu W, Kuang C, Ji F, Braun S, Liu X, Yi C, Gao F, Fahlman M. Dimensional Tailoring of Ultrahigh Vacuum Annealing-Assisted Quantum Wells for the Efficiency Enhancement of Perovskite Light-Emitting Diodes. ACS Appl Mater Interfaces 2020; 12:24965-24970. [PMID: 32394700 DOI: 10.1021/acsami.0c02217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Quasi-two-dimensional (Q-2D) perovskites featured with multidimensional quantum wells (QWs) have been the main candidates for optoelectronic applications. However, excessive low-dimensional perovskites are unfavorable to the device efficiency due to the phonon-exciton interaction and the inclusion of insulating large organic cations. Herein, the formation of low-dimensional QWs is suppressed by removing the organic cation 1-naphthylmethylamine iodide (NMAI) through ultrahigh vacuum (UHV) annealing. Perovskite light-emitting diode (PLED) devices based on films annealed with optimized UHV conditions show a higher external quantum efficiency (EQE) of 13.0% and wall-plug efficiency of 11.1% compared to otherwise identical devices with films annealed in a glovebox.
Collapse
Affiliation(s)
- Yong Yu
- Laboratory of Organic Electronics, ITN, Linköping University, Norrköping SE-60221, Sweden
| | - Heyong Wang
- Department of Physics, Chemistry and Biology, Linköping University, Linköping SE-58183, Sweden
| | - Weidong Xu
- Department of Physics, Chemistry and Biology, Linköping University, Linköping SE-58183, Sweden
| | - Chaoyang Kuang
- Department of Physics, Chemistry and Biology, Linköping University, Linköping SE-58183, Sweden
| | - Fuxiang Ji
- Department of Physics, Chemistry and Biology, Linköping University, Linköping SE-58183, Sweden
| | - Slawomir Braun
- Laboratory of Organic Electronics, ITN, Linköping University, Norrköping SE-60221, Sweden
| | - Xianjie Liu
- Laboratory of Organic Electronics, ITN, Linköping University, Norrköping SE-60221, Sweden
| | - Chang Yi
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, China
| | - Feng Gao
- Department of Physics, Chemistry and Biology, Linköping University, Linköping SE-58183, Sweden
| | - Mats Fahlman
- Laboratory of Organic Electronics, ITN, Linköping University, Norrköping SE-60221, Sweden
| |
Collapse
|
32
|
Kapoor A, Finot S, Grenier V, Robin E, Bougerol C, Bleuse J, Jacopin G, Eymery J, Durand C. Role of Underlayer for Efficient Core-Shell InGaN QWs Grown on m-plane GaN Wire Sidewalls. ACS Appl Mater Interfaces 2020; 12:19092-19101. [PMID: 32208628 DOI: 10.1021/acsami.9b19314] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Different types of buffer layers such as InGaN underlayer (UL) and InGaN/GaN superlattices are now well-known to significantly improve the efficiency of c-plane InGaN/GaN-based light-emitting diodes (LEDs). The present work investigates the role of two different kinds of pregrowth layers (low In-content InGaN UL and GaN UL namely "GaN spacer") on the emission of the core-shell m-plane InGaN/GaN single quantum well (QW) grown around Si-doped c̅-GaN microwires obtained by silane-assisted metal organic vapor phase epitaxy. According to photo- and cathodoluminescence measurements performed at room temperature, an improved efficiency of light emission at 435 nm with internal quantum efficiency >15% has been achieved by adding a GaN spacer prior to the growth of QW. As revealed by scanning transmission electron microscopy, an ultrathin residual layer containing Si located at the wire sidewall surfaces favors the formation of high density of extended defects nucleated at the first InGaN QW. This contaminated residual incorporation is buried by the growth of the GaN spacer and avoids the structural defect formation, therefore explaining the improved optical efficiency. No further improvement is observed by adding the InGaN UL to the structure, which is confirmed by comparable values of the effective carrier lifetime estimated from time-resolved experiments. Contrary to the case of planar c-plane QW where the improved efficiency is attributed to a strong decrease of point defects, the addition of an InGaN UL seems to have no influence in the case of radial m-plane QW.
Collapse
Affiliation(s)
- Akanksha Kapoor
- Université Grenoble Alpes, CEA, IRIG, PHELIQS, NPSC, Grenoble 38000, France
| | - Sylvain Finot
- Université Grenoble Alpes, CNRS, Institut Néel, Grenoble 38000, France
| | - Vincent Grenier
- Université Grenoble Alpes, CEA, IRIG, PHELIQS, NPSC, Grenoble 38000, France
| | - Eric Robin
- Université Grenoble Alpes, CEA, IRIG, MEM, LEMMA, Grenoble 38000, France
| | | | - Joel Bleuse
- Université Grenoble Alpes, CEA, IRIG, PHELIQS, NPSC, Grenoble 38000, France
| | - Gwénolé Jacopin
- Université Grenoble Alpes, CNRS, Institut Néel, Grenoble 38000, France
| | - Joël Eymery
- Université Grenoble Alpes, CEA, IRIG, MEM, NRS, Grenoble 38000, France
| | - Christophe Durand
- Université Grenoble Alpes, CEA, IRIG, PHELIQS, NPSC, Grenoble 38000, France
| |
Collapse
|
33
|
Kaku S, Ando T, Yoshino J. Real Space Imaging of Topological Edge States in InAs/GaSb and InAs/In xGa 1-xSb Quantum Wells. ACS Nano 2019; 13:12980-12986. [PMID: 31674762 DOI: 10.1021/acsnano.9b05611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Structure dependent differential tunneling conductance, dI/dV, profiles obtained using scanning tunneling microscopy on both (110)-cleaved surfaces and (001)-growth surfaces in InAs/GaSb and InAs/InxGa1-xSb quantum wells (QWs), which are platforms of two-dimensional topological insulator (2D-TI), clearly demonstrated the edge states formed on the 2D-TI surfaces. The results were confirmed by kp-based electronic structure calculations, which demonstrated that the edge states extended to the 10 nm range from cleaved surfaces generated in the appropriately designed InAs/(In)GaSb QW systems.
Collapse
Affiliation(s)
- Shigeru Kaku
- Department of Physics , Tokyo Institute of Technology , Tokyo 152-8550 , Japan
| | - Tatsuhito Ando
- Department of Physics , Tokyo Institute of Technology , Tokyo 152-8550 , Japan
| | - Junji Yoshino
- Department of Physics , Tokyo Institute of Technology , Tokyo 152-8550 , Japan
| |
Collapse
|
34
|
Luo T, Zhang Y, Xu Z, Niu T, Wen J, Lu J, Jin S, Liu SF, Zhao K. Compositional Control in 2D Perovskites with Alternating Cations in the Interlayer Space for Photovoltaics with Efficiency over 18. Adv Mater 2019; 31:e1903848. [PMID: 31523859 DOI: 10.1002/adma.201903848] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 08/18/2019] [Indexed: 05/17/2023]
Abstract
2D perovskites stabilized by alternating cations in the interlayer space (ACI) represent a very new entry as highly efficient semiconductors for solar cells approaching 15% power conversion efficiency (PCE). However, further improvements will require understanding of the nature of the films, e.g., the thickness distribution and charge-transfer characteristics of ACI quantum wells (QWs), which are currently unknown. Here, efficient control of the film quality of ACI 2D perovskite (GA)(MA)n Pbn I3 n +1 (〈n〉 = 3) QWs via incorporation of methylammonium chloride as an additive is demonstrated. The morphological and optoelectronic characterizations unambiguously demonstrate that the additive enables a larger grain size, a smoother surface, and a gradient distribution of QW thickness, which lead to enhanced photocurrent transport/extraction through efficient charge transfer between low-n and high-n QWs and suppressed nonradiative charge recombination. Therefore, the additive-treated ACI perovskite film delivers a champion PCE of 18.48%, far higher than the pristine one (15.79%) due to significant improvements in open-circuit voltage and fill factor. This PCE also stands as the highest value for all reported 2D perovskite solar cells based on the ACI, Ruddlesden-Popper, and Dion-Jacobson families. These findings establish the fundamental guidelines for the compositional control of 2D perovskites for efficient photovoltaics.
Collapse
Affiliation(s)
- Tao Luo
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, and Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, China
| | - Yalan Zhang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, and Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, China
| | - Zhuo Xu
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, and Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, China
| | - Tianqi Niu
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, and Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, China
| | - Jialun Wen
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, and Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, China
| | - Jing Lu
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, and Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, China
| | - Shengye Jin
- Dalian National Laboratory for Clean Energy, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Shengzhong Frank Liu
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, and Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, China
- Dalian National Laboratory for Clean Energy, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Kui Zhao
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, and Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, China
| |
Collapse
|
35
|
Sarzyński M, Grzanka E, Grzanka S, Targowski G, Czernecki R, Reszka A, Holy V, Nitta S, Liu Z, Amano H, Leszczyński M. Indium Incorporation into InGaN Quantum Wells Grown on GaN Narrow Stripes. Materials (Basel) 2019; 12:ma12162583. [PMID: 31416124 PMCID: PMC6719245 DOI: 10.3390/ma12162583] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 08/02/2019] [Accepted: 08/06/2019] [Indexed: 11/16/2022]
Abstract
InGaN quantum wells were grown using metalorganic chemical vapor phase epitaxy (vertical and horizontal types of reactors) on stripes made on GaN substrate. The stripe width was 5, 10, 20, 50, and 100 µm and their height was 4 and 1 µm. InGaN wells grown on stripes made in the direction perpendicular to the off-cut had a rough morphology and, therefore, this azimuth of stripes was not further explored. InGaN wells grown on the stripes made in the direction parallel to the GaN substrate off-cut had a step-flow-like morphology. For these samples (grown at low temperatures), we found out that the InGaN growth rate was higher for the narrower stripes. The higher growth rate induces a higher indium incorporation and a longer wavelength emission in photoluminescence measurements. This phenomenon is very clear for the 4 µm high stripes and less pronounced for the shallower 1 µm high stripes. The dependence of the emission wavelength on the stripe width paves a way to multicolor emitters.
Collapse
Affiliation(s)
- Marcin Sarzyński
- Institute of High Pressure Physics PAS, Sokołowska 29/37, 01-142 Warsaw, Poland.
- TopGaN Ltd., Sokołowska 29/37, 01-142 Warsaw, Poland.
| | - Ewa Grzanka
- Institute of High Pressure Physics PAS, Sokołowska 29/37, 01-142 Warsaw, Poland
- TopGaN Ltd., Sokołowska 29/37, 01-142 Warsaw, Poland
| | - Szymon Grzanka
- Institute of High Pressure Physics PAS, Sokołowska 29/37, 01-142 Warsaw, Poland
- TopGaN Ltd., Sokołowska 29/37, 01-142 Warsaw, Poland
| | - Grzegorz Targowski
- Institute of High Pressure Physics PAS, Sokołowska 29/37, 01-142 Warsaw, Poland
- TopGaN Ltd., Sokołowska 29/37, 01-142 Warsaw, Poland
| | - Robert Czernecki
- Institute of High Pressure Physics PAS, Sokołowska 29/37, 01-142 Warsaw, Poland
- TopGaN Ltd., Sokołowska 29/37, 01-142 Warsaw, Poland
| | - Anna Reszka
- Institute of Physics PAS, Al. Lotnikow 32/46, 02-668 Warsaw, Poland
| | - Vaclav Holy
- Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 121 16 Praha 2, Czech Republic
| | - Shugo Nitta
- Institute of Materials and Systems for Sustainability, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - Zhibin Liu
- Department of Electrical Engineering and Computer Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - Hiroshi Amano
- Institute of Materials and Systems for Sustainability, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
- Akasaki Research Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
- Venture Business Laboratory, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - Mike Leszczyński
- Institute of High Pressure Physics PAS, Sokołowska 29/37, 01-142 Warsaw, Poland
- TopGaN Ltd., Sokołowska 29/37, 01-142 Warsaw, Poland
| |
Collapse
|
36
|
Bi C, Wang S, Kershaw SV, Zheng K, Pullerits T, Gaponenko S, Tian J, Rogach AL. Spontaneous Self-Assembly of Cesium Lead Halide Perovskite Nanoplatelets into Cuboid Crystals with High Intensity Blue Emission. Adv Sci (Weinh) 2019; 6:1900462. [PMID: 31380191 PMCID: PMC6662087 DOI: 10.1002/advs.201900462] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 04/17/2019] [Indexed: 05/05/2023]
Abstract
Colloidal all-inorganic perovskite nanocrystals have gained significant attention as a promising material for both fundamental and applied research due to their excellent emission properties. However, reported photoluminescence quantum yields (PL QYs) of blue-emitting perovskite nanocrystals are rather low, mostly due to the fact that the high energy excitons for such wide bandgap materials are easily captured by interband traps, and then decay nonradiatively. In this work, it is demonstrated how to tackle this issue, performing self-assembly of 2D perovskite nanoplatelets into larger size (≈50 nm × 50 nm × 20 nm) cuboid crystals. In these structures, 2D nanoplatelets being isolated from each other within the cuboidal scaffold by organic ligands constitute multiple quantum wells, where exciton localization on potential disorder sites helps them to bypass nonradiative channels present in other platelets. As a result, the cuboid crystals show an extremely high PL QY of 91% of the emission band centered at 480 nm. Moreover, using the same synthetic method, mixed-anion CsPb(Br/Cl)3 cuboid crystals with blue emission peaks ranging from 452 to 470 nm, and still high PL QYs in the range of 72-83% are produced.
Collapse
Affiliation(s)
- Chenghao Bi
- Institute for Advanced Materials and TechnologyUniversity of Science and TechnologyBeijing100083China
| | - Shixun Wang
- Institute for Advanced Materials and TechnologyUniversity of Science and TechnologyBeijing100083China
- Department of Materials Science and Engineering and Centre for Functional Photonics (CFP)City University of Hong KongKowloonHong Kong S.A.R.
| | - Stephen V. Kershaw
- Department of Materials Science and Engineering and Centre for Functional Photonics (CFP)City University of Hong KongKowloonHong Kong S.A.R.
| | - Kaibo Zheng
- Department of Chemical Physics and NanoLundLund UniversityP. O. Box 12422100LundSweden
| | - Tönu Pullerits
- Department of Chemical Physics and NanoLundLund UniversityP. O. Box 12422100LundSweden
| | - Sergey Gaponenko
- B. I. Stepanov Institute of PhysicsNational Academy of Sciences of Belarus68 Nezaležnasci Ave.,220072MinskBelarus
| | - Jianjun Tian
- Institute for Advanced Materials and TechnologyUniversity of Science and TechnologyBeijing100083China
| | - Andrey L. Rogach
- Department of Materials Science and Engineering and Centre for Functional Photonics (CFP)City University of Hong KongKowloonHong Kong S.A.R.
| |
Collapse
|
37
|
Walther T. Measurement of Diffusion and Segregation in Semiconductor Quantum Dots and Quantum Wells by Transmission Electron Microscopy: A Guide. Nanomaterials (Basel) 2019; 9:E872. [PMID: 31181748 DOI: 10.3390/nano9060872] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 06/03/2019] [Accepted: 06/04/2019] [Indexed: 11/16/2022]
Abstract
Strategies are discussed to distinguish interdiffusion and segregation and to measure key parameters such as diffusivities and segregation lengths in semiconductor quantum dots and quantum wells by electron microscopy methods. Spectroscopic methods are usually necessary when the materials systems are complex while imaging methods may suffice for binary or simple ternary compounds where atomic intermixing is restricted to one type of sub-lattice. The emphasis on methodology should assist microscopists in evaluating and quantifying signals from electron micrographs and related spectroscopic data. Examples presented include CdS/ZnS core/shell particles and SiGe, InGaAs and InGaN quantum wells.
Collapse
|
38
|
Chien FC, Lo JL, Zhang X, Cubukcu E, Luo YT, Huang KL, Tang X, Chen CS, Chen CC, Lai KY. Nitride-Based Microarray Biochips: A New Route of Plasmonic Imaging. ACS Appl Mater Interfaces 2018; 10:39898-39903. [PMID: 30372020 DOI: 10.1021/acsami.8b14962] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The desire to improve human lives has led to striking development in biosensing technologies. While the ongoing research efforts are mostly dedicated to enhancing speed and sensitivity of the sensor, a third consideration that has become increasingly important is compactness, which is strongly desired in emergency situations and personal health management. Surface plasmon resonance imaging (SPRi) is one of the few techniques that can potentially fulfill all the three goals, considering its multiplexed assay capability. However, miniaturizing SPRi biosensors remains elusive as it entails complicated optical gears. Here, we significantly slim the architecture of SPRi devices by visualizing the varied local density of states around analytes. The unusual detection scheme is realized by building a gain-assisted SPRi with InGaN quantum wells (QWs), where the QW-plasmon coupling efficiency hinges on localized refractive index variation. This new modality abolishes the prism, the polarizer, and the beam-tracking components in the most used Kretschmann configuration without compromising the performances.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Xiaofang Tang
- Research Center for Applied Sciences , Academia Sinica , Taipei 11529 , Taiwan
| | - Chien-Sheng Chen
- Department of Food Safety/Hygiene and Risk Management, College of Medicine , National Cheng Kung University , Tainan 701 , Taiwan
| | | | | |
Collapse
|
39
|
Stettner T, Thurn A, Döblinger M, Hill MO, Bissinger J, Schmiedeke P, Matich S, Kostenbader T, Ruhstorfer D, Riedl H, Kaniber M, Lauhon LJ, Finley JJ, Koblmüller G. Tuning Lasing Emission toward Long Wavelengths in GaAs-(In,Al)GaAs Core-Multishell Nanowires. Nano Lett 2018; 18:6292-6300. [PMID: 30185051 DOI: 10.1021/acs.nanolett.8b02503] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Semiconductor nanowire (NW) lasers are attractive as integrated on-chip coherent light sources with strong potential for applications in optical communication and sensing. Realizing lasers from individual bulk-type NWs with emission tunable from the near-infrared to the telecommunications spectral region is, however, challenging and requires low-dimensional active gain regions with an adjustable band gap and quantum confinement. Here, we demonstrate lasing from GaAs-(InGaAs/AlGaAs) core-shell NWs with multiple InGaAs quantum wells (QW) and lasing wavelengths tunable from ∼0.8 to ∼1.1 μm. Our investigation emphasizes particularly the critical interplay between QW design, growth kinetics, and the control of InGaAs composition in the active region needed for effective tuning of the lasing wavelength. A low shell growth temperature and GaAs interlayers at the QW/barrier interfaces enable In molar fractions up to ∼25% without plastic strain relaxation or alloy intermixing in the QWs. Correlated scanning transmission electron microscopy, atom probe tomography, and confocal PL spectroscopy analyses illustrate the high sensitivity of the optically pumped lasing characteristics on microscopic properties, providing useful guidelines for other III-V-based NW laser systems.
Collapse
Affiliation(s)
- T Stettner
- Walter Schottky Institut and Physik Department , Technische Universität München , 85748 Garching , Germany
| | - A Thurn
- Walter Schottky Institut and Physik Department , Technische Universität München , 85748 Garching , Germany
| | - M Döblinger
- Department of Chemistry , Ludwig-Maximilians-Universität München , 81377 München , Germany
| | - M O Hill
- Department of Materials Science and Engineering , Northwestern University , Evanston , Illinois 60208 , United States
| | - J Bissinger
- Walter Schottky Institut and Physik Department , Technische Universität München , 85748 Garching , Germany
| | - P Schmiedeke
- Walter Schottky Institut and Physik Department , Technische Universität München , 85748 Garching , Germany
| | - S Matich
- Walter Schottky Institut and Physik Department , Technische Universität München , 85748 Garching , Germany
| | - T Kostenbader
- Walter Schottky Institut and Physik Department , Technische Universität München , 85748 Garching , Germany
| | - D Ruhstorfer
- Walter Schottky Institut and Physik Department , Technische Universität München , 85748 Garching , Germany
| | - H Riedl
- Walter Schottky Institut and Physik Department , Technische Universität München , 85748 Garching , Germany
| | - M Kaniber
- Walter Schottky Institut and Physik Department , Technische Universität München , 85748 Garching , Germany
| | - L J Lauhon
- Department of Materials Science and Engineering , Northwestern University , Evanston , Illinois 60208 , United States
| | - J J Finley
- Walter Schottky Institut and Physik Department , Technische Universität München , 85748 Garching , Germany
| | - G Koblmüller
- Walter Schottky Institut and Physik Department , Technische Universität München , 85748 Garching , Germany
| |
Collapse
|
40
|
Ortmann JE, Nookala N, He Q, Gao L, Lin C, Posadas AB, Borisevich AY, Belkin MA, Demkov AA. Quantum Confinement in Oxide Heterostructures: Room-Temperature Intersubband Absorption in SrTiO 3/LaAlO 3 Multiple Quantum Wells. ACS Nano 2018; 12:7682-7689. [PMID: 30052026 DOI: 10.1021/acsnano.8b01293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The Si-compatibility of perovskite heterostructures offers the intriguing possibility of producing oxide-based quantum well (QW) optoelectronic devices for use in Si photonics. While the SrTiO3/LaAlO3 (STO/LAO) system has been studied extensively in the hopes of using the interfacial two-dimensional electron gas in Si-integrated electronics, the potential to exploit its giant 2.4 eV conduction band offset in oxide-based QW optoelectronic devices has so far been largely ignored. Here, we demonstrate room-temperature intersubband absorption in STO/LAO QW heterostructures at energies on the order of hundreds of meV, including at energies approaching the critically important telecom wavelength of 1.55 μm. We demonstrate the ability to control the absorption energy by changing the width of the STO well layers by a single unit cell and present theory showing good agreement with experiment. A detailed structural and chemical analysis of the samples via scanning transmission electron microscopy and electron energy loss spectroscopy is presented. This work represents an important proof-of-concept for the use of transition metal oxide QWs in Si-compatible optoelectronic devices.
Collapse
Affiliation(s)
- J Elliott Ortmann
- Department of Physics , The University of Texas , Austin , Texas 78712 , United States
| | - Nishant Nookala
- Department of Electrical and Computer Engineering , The University of Texas , Austin , Texas 78712 , United States
- Microelectronics Research Center , The University of Texas at Austin , Austin , Texas 78758 , United States
| | - Qian He
- The Materials Science and Technology Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Lingyuan Gao
- Department of Physics , The University of Texas , Austin , Texas 78712 , United States
| | - Chungwei Lin
- Department of Physics , The University of Texas , Austin , Texas 78712 , United States
- Mitsubishi Electric Research Laboratories , Cambridge , Massachusetts 02139 , United States
| | - Agham B Posadas
- Department of Physics , The University of Texas , Austin , Texas 78712 , United States
| | - Albina Y Borisevich
- The Materials Science and Technology Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Mikhail A Belkin
- Department of Electrical and Computer Engineering , The University of Texas , Austin , Texas 78712 , United States
- Microelectronics Research Center , The University of Texas at Austin , Austin , Texas 78758 , United States
| | - Alexander A Demkov
- Department of Physics , The University of Texas , Austin , Texas 78712 , United States
| |
Collapse
|
41
|
Chery N, Ngo TH, Chauvat MP, Damilano B, Courville A, DE Mierry P, Grieb T, Mehrtens T, Krause FF, Müller-Caspary K, Schowalter M, Gil B, Rosenauer A, Ruterana P. The microstructure, local indium composition and photoluminescence in green-emitting InGaN/GaN quantum wells. J Microsc 2017; 268:305-312. [PMID: 29023712 DOI: 10.1111/jmi.12657] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 09/19/2017] [Accepted: 09/19/2017] [Indexed: 11/26/2022]
Abstract
In this work, we analyse the microstructure and local chemical composition of green-emitting Inx Ga1-x N/GaN quantum well (QW) heterostructures in correlation with their emission properties. Two samples of high structural quality grown by metalorganic vapour phase epitaxy (MOVPE) with a nominal composition of x = 0.15 and 0.18 indium are discussed. The local indium composition is quantitatively evaluated by comparing scanning transmission electron microscopy (STEM) images to simulations and the local indium concentration is extracted from intensity measurements. The calculations point out that the measured indium fluctuations may be correlated to the large width and intensity decrease of the PL emission peak.
Collapse
Affiliation(s)
- N Chery
- CIMAP, 6 Boulevard du Maréchal Juin, Caen, France
| | - T H Ngo
- Laboratoire Charles Coulomb, Batiment 21, Campus Triolet, Université de Montpellier, Montpellier, France
| | - M P Chauvat
- CIMAP, 6 Boulevard du Maréchal Juin, Caen, France
| | - B Damilano
- Université Côte d'Azur, CRHEA, CNRS, France
| | | | | | - T Grieb
- Institut für Festkörperphysik, Universität Bremen, Otto-Hahn-Allee 1, Bremen, Germany
| | - T Mehrtens
- Institut für Festkörperphysik, Universität Bremen, Otto-Hahn-Allee 1, Bremen, Germany
| | - F F Krause
- Institut für Festkörperphysik, Universität Bremen, Otto-Hahn-Allee 1, Bremen, Germany
| | - K Müller-Caspary
- Institut für Festkörperphysik, Universität Bremen, Otto-Hahn-Allee 1, Bremen, Germany
| | - M Schowalter
- Institut für Festkörperphysik, Universität Bremen, Otto-Hahn-Allee 1, Bremen, Germany
| | - B Gil
- Laboratoire Charles Coulomb, Batiment 21, Campus Triolet, Université de Montpellier, Montpellier, France
| | - A Rosenauer
- Institut für Festkörperphysik, Universität Bremen, Otto-Hahn-Allee 1, Bremen, Germany
| | - P Ruterana
- CIMAP, 6 Boulevard du Maréchal Juin, Caen, France
| |
Collapse
|
42
|
Abstract
Manipulating the frequency of electromagnetic waves forms the core of many modern technologies, ranging from imaging and spectroscopy to radio and optical communication. The process of converting photons from higher to lower energy is easily accomplished and technologically widespread. However, upconversion, which is the process of converting lower-energy photons into higher-energy photons, is still a growing field of study with nascent applications and burgeoning interest. Here, we experimentally demonstrate a new photon upconversion technique mediated by hot carriers in plasmonic nanostructures. Hot holes and hot electrons generated via plasmon decay in illuminated metal nanoparticles are injected into an adjacent semiconductor quantum well where they radiatively recombine to emit higher-energy photons. Using GaN/InGaN quantum wells decorated with gold and silver nanoparticles, we show photon upconversion from 2.4 to 2.8 eV. The process scales linearly with illumination power and enables both geometry- and polarization-based tunability. The conversion of plasmonic losses into upconverted optical emission has the potential to impact bioimaging, on-chip wavelength conversion, and high-efficiency photovoltaics.
Collapse
Affiliation(s)
- Gururaj V Naik
- Materials Science and Engineering, Stanford University , 496 Lomita Mall, Stanford, California 94305, United States
| | - Alex J Welch
- Materials Science and Engineering, Stanford University , 496 Lomita Mall, Stanford, California 94305, United States
| | - Justin A Briggs
- Materials Science and Engineering, Stanford University , 496 Lomita Mall, Stanford, California 94305, United States
| | - Michelle L Solomon
- Materials Science and Engineering, Stanford University , 496 Lomita Mall, Stanford, California 94305, United States
| | - Jennifer A Dionne
- Materials Science and Engineering, Stanford University , 496 Lomita Mall, Stanford, California 94305, United States
| |
Collapse
|
43
|
Bartolomé J, Hanke M, van Treeck D, Trampert A. Strain Driven Shape Evolution of Stacked (In,Ga)N Quantum Disks Embedded in GaN Nanowires. Nano Lett 2017; 17:4654-4660. [PMID: 28735548 DOI: 10.1021/acs.nanolett.7b01136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The fabrication of nanowires with axial multiquantum wells or disks presenting a homogeneous size and shape distribution along the whole stack is still an unresolved challenge, despite being essential for narrowing their light emission bandwidth. In this work we demonstrate that the commonly observed change in the shape of the disks along the stacking direction proceeds in a systematic, predictable way. High- resolution transmission electron microscopy of stacked (In,Ga)N quantum discs embedded in GaN nanowires with diameters of ∼40 nm and lengths of ∼700 nm and finite element method calculations show that, contrary to what is normally assumed, this change is not related to the radial growth of the nanowires, which is shown to be negligible, but to the strain relaxation of the whole active region. A simple model is proposed to account for the experimental observations. The model assumes that each disk reaches an equilibrium shape that minimizes the overall energy of the system, given by the sum of the surface and strain energies of the disk itself and the barrier below. The strain state of the barrier is affected by the presence of the disk buried directly below in a way that depends on its shape. This gives rise to a cumulative process, which makes the aspect ratio of each quantum disk to be smaller compared to the disk grown just before, in qualitative agreement with the experimental observations. The obtained results imply that strain relaxation is an important factor to bear in mind for the design of multiquantum disks with controlled shape along the stacking direction in any lattice mismatched nanowire system.
Collapse
Affiliation(s)
- Javier Bartolomé
- Paul-Drude-Institut für Festkörperelektronik , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - Michael Hanke
- Paul-Drude-Institut für Festkörperelektronik , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - David van Treeck
- Paul-Drude-Institut für Festkörperelektronik , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - Achim Trampert
- Paul-Drude-Institut für Festkörperelektronik , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| |
Collapse
|
44
|
Khoshakhlagh A, Gunapala SD. Infrared imaging: a potential powerful tool for neuroimaging and neurodiagnostics. Neurophotonics 2017; 4:011014. [PMID: 28382311 PMCID: PMC5369365 DOI: 10.1117/1.nph.4.1.011014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 03/14/2017] [Indexed: 05/14/2023]
Abstract
Infrared (IR) imaging is used to detect the subtle changes in temperature needed to accurately detect and monitor disease. Technological advances have made IR a highly sensitive and reliable detection tool with strong potential in medical and neurophotonics applications. An overview of IR imaging specifically investigating quantum well IR detectors developed at Jet Propulsion Laboratory for a noninvasive, nonradiating imaging tool is provided, which could be applied for neuroscience and neurosurgery where it involves sensitive cellular temperature change.
Collapse
Affiliation(s)
- Arezou Khoshakhlagh
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, United States
- Address all correspondence to: Arezou Khoshakhlagh, E-mail:
| | - Sarath D. Gunapala
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, United States
| |
Collapse
|
45
|
Kundys D, Sutherland D, Davies MJ, Oehler F, Griffiths J, Dawson P, Kappers MJ, Humphreys CJ, Schulz S, Tang F, Oliver RA. A study of the optical and polarisation properties of InGaN/GaN multiple quantum wells grown on a-plane and m-plane GaN substrates. Sci Technol Adv Mater 2016; 17:736-743. [PMID: 27933113 PMCID: PMC5127259 DOI: 10.1080/14686996.2016.1244474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 09/23/2016] [Accepted: 09/27/2016] [Indexed: 06/06/2023]
Abstract
We report on a comparative study of the low temperature emission and polarisation properties of InGaN/GaN quantum wells grown on nonpolar ([Formula: see text]) a-plane and ([Formula: see text]) m-plane free-standing bulk GaN substrates where the In content varied from 0.14 to 0.28 in the m-plane series and 0.08 to 0.21 for the a-plane series. The low temperature photoluminescence spectra from both sets of samples are broad with full width at half maximum height increasing from 81 to 330 meV as the In fraction increases. Photoluminescence excitation spectroscopy indicates that the recombination mainly involves strongly localised carriers. At 10 K the degree of linear polarisation of the a-plane samples is much smaller than of the m-plane counterparts and also varies across the spectrum. From polarisation-resolved photoluminescence excitation spectroscopy we measured the energy splitting between the lowest valence sub-bands to lie in the range of 23-54 meV for the a- and m-plane samples in which we could observe distinct exciton features. Thus the thermal occupation of a higher valence sub-band cannot be responsible for the reduction of the degree of linear polarisation at 10 K. Time-resolved spectroscopy indicates that in a-plane samples there is an extra emission component which is at least partly responsible for the reduction in the degree of linear polarisation.
Collapse
Affiliation(s)
- Dmytro Kundys
- School of Physics and Astronomy, Photon Science Institute, University of Manchester, Manchester, UK
| | - Danny Sutherland
- School of Physics and Astronomy, Photon Science Institute, University of Manchester, Manchester, UK
| | - Matthew J. Davies
- School of Physics and Astronomy, Photon Science Institute, University of Manchester, Manchester, UK
| | - Fabrice Oehler
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
| | - James Griffiths
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
| | - Philip Dawson
- School of Physics and Astronomy, Photon Science Institute, University of Manchester, Manchester, UK
| | - Menno J. Kappers
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
| | - Colin J. Humphreys
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
| | - Stefan Schulz
- Photonics Theory Group, Tyndall National Institute, Cork, Ireland
| | - Fengzai Tang
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
| | - Rachel A. Oliver
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
| |
Collapse
|
46
|
Dong S, Pal S, Lian J, Chan Y, Prezhdo OV, Loh ZH. Sub-Picosecond Auger-Mediated Hole-Trapping Dynamics in Colloidal CdSe/CdS Core/Shell Nanoplatelets. ACS Nano 2016; 10:9370-9378. [PMID: 27640430 DOI: 10.1021/acsnano.6b04210] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Quasi-two-dimensional colloidal nanoplatelets (NPLs) have recently emerged as a class of semiconductor nanomaterials whose atomically precise monodisperse thicknesses give rise to narrow absorption and emission spectra. However, the sub-picosecond carrier dynamics of NPLs at the band edge remain largely unknown, despite their importance in determining the optoelectronic properties of these materials. Here, we use a combination of femtosecond transient absorption spectroscopy and nonadiabatic molecular dynamics simulations to investigate the early time carrier dynamics of CdSe/CdS core/shell NPLs. Band-selective probing reveals sub-picosecond Auger-mediated trapping of holes with an effective second-order rate constant of 3.5 ± 1.0 cm2/s. Concomitant spectral blue shifts that are indicative of Auger hole heating are found to occur on the same time scale as the sub-picosecond trapping dynamics, whereas spectral red shifts that emerge at low excitation densities furnish an electron-cooling time scale of 0.84 ± 0.09 ps. Finally, nonadiabatic molecular dynamics simulations relate the observed sub-picosecond Auger-mediated hole-trapping dynamics to a shallow trap state that originates from the incomplete passivation of dangling bonds on the NPL surface.
Collapse
Affiliation(s)
- Shuo Dong
- Division of Chemistry and Biological Chemistry, and Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , 21 Nanyang Link, Singapore 637371
| | - Sougata Pal
- Departments of Chemistry, and Physics and Astronomy, University of Southern California , Los Angeles, California 90089, United States
| | - Jie Lian
- Institute of Materials Research & Engineering, A*STAR , 2 Fusionopolis Way, Innovis #08-03, Singapore 138634
| | - Yinthai Chan
- Institute of Materials Research & Engineering, A*STAR , 2 Fusionopolis Way, Innovis #08-03, Singapore 138634
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, Singapore 117543
| | - Oleg V Prezhdo
- Departments of Chemistry, and Physics and Astronomy, University of Southern California , Los Angeles, California 90089, United States
| | - Zhi-Heng Loh
- Division of Chemistry and Biological Chemistry, and Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , 21 Nanyang Link, Singapore 637371
| |
Collapse
|
47
|
Federspiel F, Froehlicher G, Nasilowski M, Pedetti S, Mahmood A, Doudin B, Park S, Lee JO, Halley D, Dubertret B, Gilliot P, Berciaud S. Distance dependence of the energy transfer rate from a single semiconductor nanostructure to graphene. Nano Lett 2015; 15:1252-8. [PMID: 25607231 DOI: 10.1021/nl5044192] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The near-field Coulomb interaction between a nanoemitter and a graphene monolayer results in strong Förster-type resonant energy transfer and subsequent fluorescence quenching. Here, we investigate the distance dependence of the energy transfer rate from individual, (i) zero-dimensional CdSe/CdS nanocrystals and (ii) two-dimensional CdSe/CdS/ZnS nanoplatelets to a graphene monolayer. For increasing distances d, the energy transfer rate from individual nanocrystals to graphene decays as 1/d(4). In contrast, the distance dependence of the energy transfer rate from a two-dimensional nanoplatelet to graphene deviates from a simple power law but is well described by a theoretical model, which considers a thermal distribution of free excitons in a two-dimensional quantum well. Our results show that accurate distance measurements can be performed at the single particle level using graphene-based molecular rulers and that energy transfer allows probing dimensionality effects at the nanoscale.
Collapse
Affiliation(s)
- François Federspiel
- Institut de Physique et Chimie des Matériaux de Strasbourg and NIE, UMR 7504, Université de Strasbourg and CNRS , 23 rue du Lœss, BP43, 67034 Strasbourg Cedex 2, France
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Abstract
Layered hybrid organic perovskites (HOPs) structures are a class of low-cost two-dimensional materials that exhibit outstanding optical properties, related to dielectric and quantum confinement effects. Whereas modeling and understanding of quantum confinement are well developed for conventional semiconductors, such knowledge is still lacking for 2D HOPs. In this work, concepts of effective mass and quantum well are carefully investigated and their applicability to 2D HOPs is discussed. For ultrathin layers, the effective-mass model fails. Absence of superlattice coupling and importance of non-parabolicity effects prevents the use of simple empirical models based on effective masses and envelope function approximations. An alternative method is suggested in which 2D HOPs are treated as composite materials, and a first-principles approach to the calculation of band offsets is introduced. These findings might also be relevant for other classes of layered 2D functional materials.
Collapse
Affiliation(s)
- Jacky Even
- Université Européenne de Bretagne, FOTON UMR 6082 CNRS-INSA de Rennes, 35708 Rennes (France).
| | | | | |
Collapse
|
49
|
Wang Z, Wang T, Wang H, Yan D. An organic quantum well based on high-quality crystalline heteroepitaxy films. Adv Mater 2014; 26:4582-4587. [PMID: 24824163 DOI: 10.1002/adma.201400702] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 04/03/2014] [Indexed: 06/03/2023]
Abstract
A meaningful organic quantum well based on crystalline heteroepitaxy films is constructed. The quantum confinement effect is demonstrated by its reflections on optics and electrics: the blueshift of the optical characteristic peaks and the negative differential resistance at room temperature. The realization of an organic quantum well indicates the highly delocalized transport mechanism in well-defined organic crystalline systems and promises novel organic "quantum" optoelectronic devices.
Collapse
Affiliation(s)
- Zi Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China; University of Chinese Academy of Sciences, Beijing, 100039, China
| | | | | | | |
Collapse
|
50
|
Baranowski M, Kudrawiec R, Syperek M, Misiewicz J, Sarmiento T, Harris JS. Time-resolved photoluminescence studies of annealed 1.3-μm GaInNAsSb quantum wells. Nanoscale Res Lett 2014; 9:81. [PMID: 24533740 PMCID: PMC3942105 DOI: 10.1186/1556-276x-9-81] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 02/03/2014] [Indexed: 06/03/2023]
Abstract
Time-resolved photoluminescence (PL) was applied to study the dynamics of carrier recombination in GaInNAsSb quantum wells (QWs) emitting near 1.3 μm and annealed at various temperatures. It was observed that the annealing temperature has a strong influence on the PL decay time, and hence, it influences the optical quality of GaInNAsSb QWs. At low temperatures, the PL decay time exhibits energy dependence (i.e., the decay times change for different energies of emitted photons), which can be explained by the presence of localized states. This energy dependence of PL decay times was fitted by a phenomenological formula, and the average value of E0, which describes the energy distribution of localized states, was extracted from this fit and found to be smallest (E0 = 6 meV) for the QW annealed at 700°C. In addition, the value of PL decay time at the peak energy was compared for all samples. The longest PL decay time (600 ps) was observed for the sample annealed at 700°C. It means that based on the PL dynamics, the optimal annealing temperature for this QW is approximately 700°C.
Collapse
Affiliation(s)
- Michal Baranowski
- Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, Wroclaw 50-370, Poland
| | - Robert Kudrawiec
- Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, Wroclaw 50-370, Poland
| | - Marcin Syperek
- Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, Wroclaw 50-370, Poland
| | - Jan Misiewicz
- Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, Wroclaw 50-370, Poland
| | - Tomas Sarmiento
- Solid State and Photonics Laboratory, Stanford University, Stanford, CA 94305-4075, USA
| | - James S Harris
- Solid State and Photonics Laboratory, Stanford University, Stanford, CA 94305-4075, USA
| |
Collapse
|