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Allegro I, Bonal V, Mamleyev ER, Villalvilla JM, Quintana JA, Jin Q, Díaz-García MA, Lemmer U. Distributed Feedback Lasers by Thermal Nanoimprint of Perovskites Using Gelatin Gratings. ACS Appl Mater Interfaces 2023; 15:8436-8445. [PMID: 36720173 PMCID: PMC9940720 DOI: 10.1021/acsami.2c22920] [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: 12/21/2022] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
To date, thermal nanoimprint lithography (NIL) for patterning hybrid perovskites has always involved an intricate etching step of a hard stamp material or its master. Here, we demonstrate for the first time the successful nanopatterning of a perovskite film by NIL with a low-cost polymeric stamp. The stamp consists of a dichromated gelatin grating structured by holographic lithography. The one-dimensional grating is imprinted into a perovskite film at 95 °C and 90 MPa for 10 min, resulting in a high quality second-order distributed feedback (DFB) laser. The laser exhibits an excellent performance with a threshold of 81 μJ/cm2, a line width of 0.32 nm, and a pronounced linear polarization. This novel approach enables cost-effective fabrication of high-quality DFB lasers compatible with different perovskite compositions and photonic nanostructures for a wide range of applications.
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Affiliation(s)
- Isabel Allegro
- Light
Technology Institute, Karlsruhe Institute
of Technology, Engesserstrasse 13, 76131Karlsruhe, Germany
| | - Víctor Bonal
- Departamento
de Física Aplicada and Instituto Universitario de Materiales
de Alicante (IUMA), Universidad de Alicante, 03080Alicante, Spain
| | - Emil R. Mamleyev
- Institute
of Microstructure Technology, Karlsruhe
Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344Eggenstein-Leopoldshafen, Germany
| | - José M. Villalvilla
- Departamento
de Física Aplicada and Instituto Universitario de Materiales
de Alicante (IUMA), Universidad de Alicante, 03080Alicante, Spain
| | - José A. Quintana
- Departamento
de Óptica, Farmacología y Anatomía,
and IUMA, Universidad de Alicante, 03080Alicante, Spain
| | - Qihao Jin
- Light
Technology Institute, Karlsruhe Institute
of Technology, Engesserstrasse 13, 76131Karlsruhe, Germany
| | - María A. Díaz-García
- Departamento
de Física Aplicada and Instituto Universitario de Materiales
de Alicante (IUMA), Universidad de Alicante, 03080Alicante, Spain
| | - Uli Lemmer
- Light
Technology Institute, Karlsruhe Institute
of Technology, Engesserstrasse 13, 76131Karlsruhe, Germany
- Institute
of Microstructure Technology, Karlsruhe
Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344Eggenstein-Leopoldshafen, Germany
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2
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Zhai T, Ma X, Han L, Zhang S, Ge K, Xu Y, Xu Z, Cui L. Self-Aligned Emission of Distributed Feedback Lasers on Optical Fiber Sidewall. Nanomaterials (Basel) 2021; 11:nano11092381. [PMID: 34578697 PMCID: PMC8470634 DOI: 10.3390/nano11092381] [Citation(s) in RCA: 3] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 09/09/2021] [Accepted: 09/11/2021] [Indexed: 12/27/2022]
Abstract
This article assembles a distributed feedback (DFB) cavity on the sidewalls of the optical fiber by using very simple fabrication techniques including two-beam interference lithography and dip-coating. The DFB laser structure comprises graduated gratings on the optical fiber sidewalls which are covered with a layer of colloidal quantum dots. Directional DFB lasing is observed from the fiber facet due to the coupling effect between the grating and the optical fiber. The directional lasing from the optical fiber facet exhibits a small solid divergence angle as compared to the conventional laser. It can be attributed to the two-dimensional light confinement in the fiber waveguide. An analytical approach based on the Bragg condition and the coupled-wave theory was developed to explain the characteristics of the laser device. The intensity of the output coupled laser is tuned by the coupling coefficient, which is determined by the angle between the grating vector and the fiber axis. These results afford opportunities to integrate different DFB lasers on the same optical fiber sidewall, achieving multi-wavelength self-aligned DFB lasers for a directional emission. The proposed technique may provide an alternative to integrating DFB lasers for applications in networking, optical sensing, and power delivery.
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3
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Nie L, Ng WK, Liang Z, Ren X, Yang T, Mei G, Leung CW, Wong KS, Choy WCH. Upside-Down Molding Approach for Geometrical Parameter-Tunable Photonic Perovskite Nanostructures. ACS Appl Mater Interfaces 2021; 13:27313-27322. [PMID: 34100286 DOI: 10.1021/acsami.1c02318] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Considering that the periodic photonic nanostructures are commonly realized by expensive nanofabrication processes and the tunability of structure parameters is limited and complicated, we demonstrate a solution-processed upside-down molding method to fabricate photonic resonators on perovskites with a pattern geometry controllable to a certain extent. This upside-down approach not only reveals the effect of capillary force during the imprinting but also can control the waveguide layer thickness due to the inversion of the perovskite membranes.
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Affiliation(s)
- Lebin Nie
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, Special Administrative Region 999077, China
| | - Wai Kit Ng
- Department of Physics and and William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, Clear Way Bay, Hong Kong, Special Administrative Region 999077, China
| | - ZhiFu Liang
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, Special Administrative Region 999077, China
| | - Xingang Ren
- Key Laboratory of Intelligent Computing & Signal Processing, Anhui University, Hefei 230036, China
| | - Tingbin Yang
- Core Research Facilities, Southern University of Science and Technology, Shenzhen 518055, China
| | - Guanding Mei
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, Special Administrative Region 999077, China
| | - Chi Wah Leung
- Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong Special Administrative Region 999077, China
| | - Kam Sing Wong
- Department of Physics and and William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, Clear Way Bay, Hong Kong, Special Administrative Region 999077, China
| | - Wallace C H Choy
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, Special Administrative Region 999077, China
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4
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Pourdavoud N, Haeger T, Mayer A, Cegielski PJ, Giesecke AL, Heiderhoff R, Olthof S, Zaefferer S, Shutsko I, Henkel A, Becker-Koch D, Stein M, Cehovski M, Charfi O, Johannes HH, Rogalla D, Lemme MC, Koch M, Vaynzof Y, Meerholz K, Kowalsky W, Scheer HC, Görrn P, Riedl T. Room-Temperature Stimulated Emission and Lasing in Recrystallized Cesium Lead Bromide Perovskite Thin Films. Adv Mater 2019; 31:e1903717. [PMID: 31402527 DOI: 10.1002/adma.201903717] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 07/15/2019] [Indexed: 05/18/2023]
Abstract
Cesium lead halide perovskites are of interest for light-emitting diodes and lasers. So far, thin-films of CsPbX3 have typically afforded very low photoluminescence quantum yields (PL-QY < 20%) and amplified spontaneous emission (ASE) only at cryogenic temperatures, as defect related nonradiative recombination dominated at room temperature (RT). There is a current belief that, for efficient light emission from lead halide perovskites at RT, the charge carriers/excitons need to be confined on the nanometer scale, like in CsPbX3 nanoparticles (NPs). Here, thin films of cesium lead bromide, which show a high PL-QY of 68% and low-threshold ASE at RT, are presented. As-deposited layers are recrystallized by thermal imprint, which results in continuous films (100% coverage of the substrate), composed of large crystals with micrometer lateral extension. Using these layers, the first cesium lead bromide thin-film distributed feedback and vertical cavity surface emitting lasers with ultralow threshold at RT that do not rely on the use of NPs are demonstrated. It is foreseen that these results will have a broader impact beyond perovskite lasers and will advise a revision of the paradigm that efficient light emission from CsPbX3 perovskites can only be achieved with NPs.
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Affiliation(s)
- Neda Pourdavoud
- Institute of Electronic Devices, University of Wuppertal, Rainer-Gruenter-Str. 21, 42119, Wuppertal, Germany
| | - Tobias Haeger
- Institute of Electronic Devices, University of Wuppertal, Rainer-Gruenter-Str. 21, 42119, Wuppertal, Germany
| | - Andre Mayer
- Chair of Large Area Optoelectronics, University of Wuppertal, Rainer-Gruenter-Str. 21, 42119, Wuppertal, Germany
| | - Piotr Jacek Cegielski
- AMO GmbH, Otto-Blumenthal-Straße 25, 52074, Aachen, Germany
- Elektrotechnik und Informationstechnik, Lehrstuhl für Elektronische Bauelemente, RWTH Aachen University, Otto-Blumenthal-Straße 25, 52074, Aachen, Germany
| | | | - Ralf Heiderhoff
- Institute of Electronic Devices, University of Wuppertal, Rainer-Gruenter-Str. 21, 42119, Wuppertal, Germany
| | - Selina Olthof
- Department of Chemistry, University of Cologne, Luxemburger Straße 116, 50939, Cologne, Germany
| | - Stefan Zaefferer
- Max-Planck-Institut für Eisenforschung, Max-Planck-Str. 1, 40237, Düsseldorf, Germany
| | - Ivan Shutsko
- Chair of Large Area Optoelectronics, University of Wuppertal, Rainer-Gruenter-Str. 21, 42119, Wuppertal, Germany
| | - Andreas Henkel
- Chair of Large Area Optoelectronics, University of Wuppertal, Rainer-Gruenter-Str. 21, 42119, Wuppertal, Germany
| | - David Becker-Koch
- Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 227, 69120, Heidelberg, Germany
- Center for Advanced Materials, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 225, 69120, Heidelberg, Germany
| | - Markus Stein
- Fachbereich Physik, Philipps-Universität Marburg, Renthof 5, 35032, Marburg, Germany
| | - Marko Cehovski
- Institut für Hochfrequenztechnik, Technische Universität Braunschweig, Schleinitzstr. 22, 38106, Braunschweig, Germany
- Cluster of Excellence PhoenixD (Photonics, Optics, and Engineering - Innovation Across Disciplines), Welfengarten 1, 30167, Hannover, Germany
| | - Ouacef Charfi
- Institut für Hochfrequenztechnik, Technische Universität Braunschweig, Schleinitzstr. 22, 38106, Braunschweig, Germany
- Cluster of Excellence PhoenixD (Photonics, Optics, and Engineering - Innovation Across Disciplines), Welfengarten 1, 30167, Hannover, Germany
| | - Hans-Hermann Johannes
- Institut für Hochfrequenztechnik, Technische Universität Braunschweig, Schleinitzstr. 22, 38106, Braunschweig, Germany
- Cluster of Excellence PhoenixD (Photonics, Optics, and Engineering - Innovation Across Disciplines), Welfengarten 1, 30167, Hannover, Germany
| | - Detlef Rogalla
- RUBION, Ruhr-University Bochum, D-44801, Bochum, Germany
| | - Max Christian Lemme
- AMO GmbH, Otto-Blumenthal-Straße 25, 52074, Aachen, Germany
- Elektrotechnik und Informationstechnik, Lehrstuhl für Elektronische Bauelemente, RWTH Aachen University, Otto-Blumenthal-Straße 25, 52074, Aachen, Germany
| | - Martin Koch
- Fachbereich Physik, Philipps-Universität Marburg, Renthof 5, 35032, Marburg, Germany
| | - Yana Vaynzof
- Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 227, 69120, Heidelberg, Germany
- Center for Advanced Materials, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 225, 69120, Heidelberg, Germany
| | - Klaus Meerholz
- Department of Chemistry, University of Cologne, Luxemburger Straße 116, 50939, Cologne, Germany
| | - Wolfgang Kowalsky
- Institut für Hochfrequenztechnik, Technische Universität Braunschweig, Schleinitzstr. 22, 38106, Braunschweig, Germany
- Cluster of Excellence PhoenixD (Photonics, Optics, and Engineering - Innovation Across Disciplines), Welfengarten 1, 30167, Hannover, Germany
| | - Hella-Christin Scheer
- Chair of Large Area Optoelectronics, University of Wuppertal, Rainer-Gruenter-Str. 21, 42119, Wuppertal, Germany
| | - Patrick Görrn
- Chair of Large Area Optoelectronics, University of Wuppertal, Rainer-Gruenter-Str. 21, 42119, Wuppertal, Germany
| | - Thomas Riedl
- Institute of Electronic Devices, University of Wuppertal, Rainer-Gruenter-Str. 21, 42119, Wuppertal, Germany
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5
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Zhang Q, Wei Q, Guo X, Hai G, Sun H, Li J, Xia R, Qian Y, Casado S, Castro‐Smirnov JR, Cabanillas‐Gonzalez J. Concurrent Optical Gain Optimization and Electrical Tuning in Novel Oligomer:Polymer Blends with Yellow-Green Laser Emission. Adv Sci (Weinh) 2019; 6:1801455. [PMID: 30643727 PMCID: PMC6325601 DOI: 10.1002/advs.201801455] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [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: 08/29/2018] [Revised: 09/27/2018] [Indexed: 06/09/2023]
Abstract
Electrically pumped organic lasing requires the integration of electrodes contact into the laser cavity in an organic light-emitting diode (OLED) or organic field effect transistor configuration to enable charge injection. Efficient and balanced carrier injection requires in turn alignment of the energy levels of the organic active layers with the Fermi levels of the cathode and anode. This can be achieved through chemical substitution with specific aromatic functional groups, although paying the price for a substantial (and often detrimental) change in the emission and light amplifying properties of the organic gain medium. Here, using host-guest energy transfer mixtures with hosts bearing a systematic and gradual shift in molecular orbitals is proposed, which reduces the amplified spontaneous emission (ASE) threshold of the organic gain medium significantly while leaving the peak emission unaffected. By virtue of the low guest doping required for complete host-to-guest energy transfer, the injection levels in the blends are attributed to the host whereas the gain properties solely depend on the guest. It is demonstrated that the ASE peak and thresholds of blends with different hosts do not differ while the current efficiency of OLEDs devices is deeply influenced by molecular orbital tuning of the hosts.
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Affiliation(s)
- Qi Zhang
- Key Laboratory for Organic Electronics and Information Displays (KLOEID)Jiangsu‐Singapore Joint Research Center for Organic/Bio Electronics and Information DisplaysInstitute of Advanced Materials (IAM)Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing210046P. R. China
- IMDEA NanoscienceCalle Faraday 9Cantoblanco28049MadridSpain
| | - Qi Wei
- Shaanxi Institute of Flexible Electronics (SIFE)Northwestern Polytechnical University (NPU)127 West Youyi RoadXi'an710072ShanxiChina
| | - Xiangru Guo
- Key Laboratory for Organic Electronics and Information Displays (KLOEID)Jiangsu‐Singapore Joint Research Center for Organic/Bio Electronics and Information DisplaysInstitute of Advanced Materials (IAM)Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing210046P. R. China
| | - Gang Hai
- Key Laboratory for Organic Electronics and Information Displays (KLOEID)Jiangsu‐Singapore Joint Research Center for Organic/Bio Electronics and Information DisplaysInstitute of Advanced Materials (IAM)Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing210046P. R. China
| | - Huizhi Sun
- Key Laboratory for Organic Electronics and Information Displays (KLOEID)Jiangsu‐Singapore Joint Research Center for Organic/Bio Electronics and Information DisplaysInstitute of Advanced Materials (IAM)Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing210046P. R. China
| | - Jiewei Li
- Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM)Jiangsu National Synergistic Innovation Center for Advanced Materials (SICAM)Nanjing Tech University (NanjingTech)30 South Puzhu RoadNanjing211816China
| | - Ruidong Xia
- Key Laboratory for Organic Electronics and Information Displays (KLOEID)Jiangsu‐Singapore Joint Research Center for Organic/Bio Electronics and Information DisplaysInstitute of Advanced Materials (IAM)Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing210046P. R. China
| | - Yan Qian
- Key Laboratory for Organic Electronics and Information Displays (KLOEID)Jiangsu‐Singapore Joint Research Center for Organic/Bio Electronics and Information DisplaysInstitute of Advanced Materials (IAM)Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing210046P. R. China
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6
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Zhang L, Liao C, Lv B, Wang X, Xiao M, Xu R, Yuan Y, Lu C, Cui Y, Zhang J. Single-Mode Lasing from "Giant" CdSe/CdS Core-Shell Quantum Dots in Distributed Feedback Structures. ACS Appl Mater Interfaces 2017; 9:13293-13303. [PMID: 28357855 DOI: 10.1021/acsami.7b01669] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
"Giant" semiconductor quantum dots (GQDs) have tremendous potential for applications in laser devices. Here, CdSe/CdS core-shell GQDs (11 monolayers) have been synthesized as lasing gain material. The photoluminescence decay of the GQD ensemble is single-exponential, and the two-photon absorption cross-section is above 105 GM. This article presents a versatile method for fabrication of CdSe/CdS GQD distributed feedback (DFB) lasers by laser interference ablation. A high-quality surface-relief grating structure can be readily created on the GQD thin films, and the relationship between laser beam intensity and surface modulation depth is studied. With appropriate periods, single-mode lasing emission has been detected from these devices under excitation wavelengths of 400 and 800 nm. The laser thresholds are as low as 0.028 and 1.03 mJ cm-2, with the lasing Q-factors of 709 and 586, respectively. Lasing operation is realized from the direct laser interference-ablated QD DFB structures for the first time.
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Affiliation(s)
- Lei Zhang
- Advanced Photonics Center, School of Electronic Science & Engineering, Southeast University , Nanjing 210096, China
| | - Chen Liao
- Advanced Photonics Center, School of Electronic Science & Engineering, Southeast University , Nanjing 210096, China
| | - Bihu Lv
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University , Nanjing 210093, China
| | - Xiaoyong Wang
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University , Nanjing 210093, China
| | - Min Xiao
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University , Nanjing 210093, China
| | - Ruilin Xu
- Advanced Photonics Center, School of Electronic Science & Engineering, Southeast University , Nanjing 210096, China
| | - Yufen Yuan
- Advanced Photonics Center, School of Electronic Science & Engineering, Southeast University , Nanjing 210096, China
| | - Changgui Lu
- Advanced Photonics Center, School of Electronic Science & Engineering, Southeast University , Nanjing 210096, China
| | - Yiping Cui
- Advanced Photonics Center, School of Electronic Science & Engineering, Southeast University , Nanjing 210096, China
| | - Jiayu Zhang
- Advanced Photonics Center, School of Electronic Science & Engineering, Southeast University , Nanjing 210096, China
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7
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Saliba M, Wood SM, Patel JB, Nayak PK, Huang J, Alexander-Webber JA, Wenger B, Stranks SD, Hörantner MT, Wang JTW, Nicholas RJ, Herz LM, Johnston MB, Morris SM, Snaith HJ, Riede MK. Structured Organic-Inorganic Perovskite toward a Distributed Feedback Laser. Adv Mater 2016; 28:923-9. [PMID: 26630410 DOI: 10.1002/adma.201502608] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 10/14/2015] [Indexed: 05/24/2023]
Abstract
A general strategy for the in-plane structuring of organic-inorganic perovskite films is presented. The method is used to fabricate an industrially relevant distributed feedback (DFB) cavity, which is a critical step toward all-electrially pumped injection laser diodes. This approach opens the prospects of perovskite materials for much improved optical control in LEDs, solar cells, and also toward applications as optical devices.
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Affiliation(s)
- Michael Saliba
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | - Simon M Wood
- Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, UK
| | - Jay B Patel
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | - Pabitra K Nayak
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | - Jian Huang
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | | | - Bernard Wenger
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | - Samuel D Stranks
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | | | - Jacob Tse-Wei Wang
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | - Robin J Nicholas
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | - Laura M Herz
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | - Michael B Johnston
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | - Stephen M Morris
- Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, UK
| | - Henry J Snaith
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | - Moritz K Riede
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
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