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Sukkabot W. Observation of spin-splitting energies on sp-d exchange interactions tailored in colloidal CdSe/CdMnS core/shell nanoplatelets: an atomistic tight-binding model. Phys Chem Chem Phys 2024; 26:11807-11814. [PMID: 38566596 DOI: 10.1039/d4cp00353e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Using the atomistic tight-binding model plus sp-d exchange term, the embedding of magnetic ions into CdSe/CdMnS core/shell nanoplatelets (NPLs) at different effective temperatures resulted in sp-d exchange interactions, which in turn cause modifications in electronic and magnetic characteristics. The influence of CdMnS monolayers on single-particle spectra, optical band gaps, wave function overlaps and exciton binding energies is more pronounced than that of the effective temperature. Due to the electron, hole and Zeeman splitting energies, with the growth of CdMnS shell monolayers, electron g-factor values are unchanged, but hole and exciton g-factor values are enhanced. Additionally, all g values decrease with increasing temperature, thus representing decreased magnetization of the paramagnetic system. By changing nanoplatelet architectures and temperatures, manipulation of s-d and p-d exchange interactions is accomplished. Overall, studied materials combine the merits of NPLs and magnetic ions, hence leading to alternate possibilities for active applications in spin-based devices.
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Affiliation(s)
- Worasak Sukkabot
- Department of Physics, Faculty of Science, Ubon Ratchathani University, 85 Sathollmark Rd. Warinchamrab, Ubon Ratchathani 34190, Thailand.
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2
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Dehnel J, Harchol A, Barak Y, Meir I, Horani F, Shapiro A, Strassberg R, de Mello Donegá C, Demir HV, Gamelin DR, Sharma K, Lifshitz E. Optically detected magnetic resonance spectroscopic analyses on the role of magnetic ions in colloidal nanocrystals. J Chem Phys 2023; 159:071001. [PMID: 37581419 DOI: 10.1063/5.0160787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 07/26/2023] [Indexed: 08/16/2023] Open
Abstract
Incorporating magnetic ions into semiconductor nanocrystals has emerged as a prominent research field for manipulating spin-related properties. The magnetic ions within the host semiconductor experience spin-exchange interactions with photogenerated carriers and are often involved in the recombination routes, stimulating special magneto-optical effects. The current account presents a comparative study, emphasizing the impact of engineering nanostructures and selecting magnetic ions in shaping carrier-magnetic ion interactions. Various host materials, including the II-VI group, halide perovskites, and I-III-VI2 in diverse structural configurations such as core/shell quantum dots, seeded nanorods, and nanoplatelets, incorporated with magnetic ions such as Mn2+, Ni2+, and Cu1+/2+ are highlighted. These materials have recently been investigated by us using state-of-the-art steady-state and transient optically detected magnetic resonance (ODMR) spectroscopy to explore individual spin-dynamics between the photogenerated carriers and magnetic ions and their dependence on morphology, location, crystal composition, and type of the magnetic ion. The information extracted from the analyses of the ODMR spectra in those studies exposes fundamental physical parameters, such as g-factors, exchange coupling constants, and hyperfine interactions, together providing insights into the nature of the carrier (electron, hole, dopant), its local surroundings (isotropic/anisotropic), and spin dynamics. The findings illuminate the importance of ODMR spectroscopy in advancing our understanding of the role of magnetic ions in semiconductor nanocrystals and offer valuable knowledge for designing magnetic materials intended for various spin-related technologies.
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Affiliation(s)
- Joanna Dehnel
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Adi Harchol
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Yahel Barak
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Itay Meir
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Faris Horani
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
| | - Arthur Shapiro
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
- Optical Materials Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, 8092 Zurich, Switzerland
| | - Rotem Strassberg
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Celso de Mello Donegá
- Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science, Utrecht University, 3584 CC Utrecht, The Netherlands
| | - Hilmi Volkan Demir
- Luminous Center of Excellence for Semiconductor Lighting and Displays, TPI, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, School of Materials Science and Engineering, Nanyang Technological University-NTU Singapore, 639798, Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM-Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Türkiye
| | - Daniel R Gamelin
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
| | - Kusha Sharma
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Efrat Lifshitz
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
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3
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Babunts RA, Uspenskaya YA, Romanov NG, Orlinskii SB, Mamin GV, Shornikova EV, Yakovlev DR, Bayer M, Isik F, Shendre S, Delikanli S, Demir HV, Baranov PG. High-Frequency EPR and ENDOR Spectroscopy of Mn 2+ Ions in CdSe/CdMnS Nanoplatelets. ACS NANO 2023; 17:4474-4482. [PMID: 36802485 DOI: 10.1021/acsnano.2c10123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Semiconductor colloidal nanoplatelets based of CdSe have excellent optical properties. Their magneto-optical and spin-dependent properties can be greatly modified by implementing magnetic Mn2+ ions, using concepts well established for diluted magnetic semiconductors. A variety of magnetic resonance techniques based on high-frequency (94 GHz) electron paramagnetic resonance in continuous wave and pulsed mode were used to get detailed information on the spin structure and spin dynamics of Mn2+ ions in core/shell CdSe/(Cd,Mn)S nanoplatelets. We observed two sets of resonances assigned to the Mn2+ ions inside the shell and at the nanoplatelet surface. The surface Mn demonstrates a considerably longer spin dynamics than the inner Mn due to lower amount of surrounding Mn2+ ions. The interaction between surface Mn2+ ions and 1H nuclei belonging to oleic acid ligands is measured by means of electron nuclear double resonance. This allowed us to estimate the distances between the Mn2+ ions and 1H nuclei, which equal to 0.31 ± 0.04, 0.44 ± 0.09, and more than 0.53 nm. This study shows that the Mn2+ ions can serve as atomic-size probes for studying the ligand attachment to the nanoplatelet surface.
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Affiliation(s)
- Roman A Babunts
- Ioffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia
| | - Yulia A Uspenskaya
- Ioffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia
| | - Nikolai G Romanov
- Ioffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia
| | | | - Georgy V Mamin
- Kazan Federal University, Institute of Physics, 420008 Kazan, Russia
| | - Elena V Shornikova
- Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, Germany
| | - Dmitri R Yakovlev
- Ioffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia
- Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, Germany
| | - Manfred Bayer
- Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, Germany
| | - Furkan Isik
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology, Bilkent University, 06800 Ankara, Turkey
| | - Sushant Shendre
- Luminous! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, School of Materials Science and Engineering, Nanyang Technological University, 639798 Singapore
| | - Savas Delikanli
- Luminous! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, School of Materials Science and Engineering, Nanyang Technological University, 639798 Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology, Bilkent University, 06800 Ankara, Turkey
| | - Hilmi Volkan Demir
- Luminous! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, School of Materials Science and Engineering, Nanyang Technological University, 639798 Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology, Bilkent University, 06800 Ankara, Turkey
| | - Pavel G Baranov
- Ioffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia
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Li C, Hsu SC, Lin JX, Chen JY, Chuang KC, Chang YP, Hsu HS, Chen CH, Lin TS, Liu YH. Giant Zeeman Splitting for Monolayer Nanosheets at Room Temperature. J Am Chem Soc 2020; 142:20616-20623. [PMID: 33249824 DOI: 10.1021/jacs.0c05368] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Giant Zeeman splitting and zero-field splitting (ZFS) are observed in 2D nanosheets that have monolayers of atomic thickness. In this study, single-crystalline CdSe(ethylenediamine)0.5 and Mn2+-doped nanosheets are synthesized via a solvothermal process. Tunable amounts of Mn2+(0.5-8.0%) are introduced, resulting in lattice contraction as well as phosphorescence from five unpaired electrons. The exciton dynamics are dominated by spin-related electronic transitions (4T1 → 6A1) with long lifetimes (20.5, 132, and 295 μs). Temperature-varied EPR spectroscopy with spectral simulation reveals large ZFS (D = 3850 MHz) due to axial distortion of substituted Mn2+ (S = 5/2). In the magnetic circular dichroism (MCD) measurements, we observed giant Zeeman splitting with large effective g values (up to 231 ± 21), which implies huge sp-d exchange interactions in 2D monolayer regimes, leading to diluted magnetic semiconductor (DMS) materials.
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Affiliation(s)
- Chi Li
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan, ROC
| | - Sheng-Chih Hsu
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan, ROC
| | - Jun-Xiao Lin
- Department of Applied Physics, National Pingtung University, Pingtung 90003, Taiwan, ROC
| | - Jou-Yun Chen
- Department of Chemistry, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan, ROC
| | - Kai-Chun Chuang
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan, ROC
| | - Yuan-Pin Chang
- Department of Chemistry, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan, ROC
| | - Hua-Shu Hsu
- Department of Applied Physics, National Pingtung University, Pingtung 90003, Taiwan, ROC
| | - Ching-Hsiang Chen
- Graduate Institute of Applied Science and Technology, National Taiwan University of Science & Technology, Taipei 10673, Taiwan, ROC
| | - Tien-Sung Lin
- Department of Chemistry, Washington University, Saint Louis, Missouri 63130, United States
| | - Yi-Hsin Liu
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan, ROC
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5
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Tolmachev DO, Ivanov VY, Yakovlev DR, Shornikova EV, Witkowski B, Shendre S, Isik F, Delikani S, Demir HV, Bayer M. Optically detected magnetic resonance in CdSe/CdMnS nanoplatelets. NANOSCALE 2020; 12:21932-21939. [PMID: 33112343 DOI: 10.1039/d0nr05633b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Core/shell CdSe/(Cd,Mn)S colloidal nanoplatelets containing magnetic Mn2+ ions are investigated by the optically detected magnetic resonance technique, combining 60 GHz microwave excitation and photoluminescence detection. Resonant heating of the Mn spin system is observed. We identify two mechanisms of optical detection, via variation of either the photoluminescence polarization or its intensity in an external magnetic field. The spin-lattice relaxation dynamics of the Mn spin system is measured and used for evaluation of the Mn concentration. In CdSe/(Cd,Zn,Mn)S nanoplatelets the addition of Zn in the shells significantly broadens the magnetic resonance, evidencing local strain.
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Affiliation(s)
- Danil O Tolmachev
- Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, Germany.
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6
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Dehnel J, Barak Y, Meir I, Budniak AK, Nagvenkar AP, Gamelin DR, Lifshitz E. Insight into the Spin Properties in Undoped and Mn-Doped CdSe/CdS-Seeded Nanorods by Optically Detected Magnetic Resonance. ACS NANO 2020; 14:13478-13490. [PMID: 32935976 DOI: 10.1021/acsnano.0c05454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Controlling the spin degrees of freedom of photogenerated species in semiconductor nanostructures via magnetic doping is an emerging scientific field that may play an important role in the development of new spin-based technologies. The current work explores spin properties in colloidal CdSe/CdS:Mn seeded-nanorod structures doped with a dilute concentration of Mn2+ ions across the rods. The spin properties were determined using continuous-wave optically detected magnetic resonance (ODMR) spectroscopy recorded under variable microwave chopping frequencies. These experiments enabled the deconvolution of a few different radiative recombination processes: band-to-band, trap-to-band, and trap-to-trap emission. The results uncovered the major role of carrier trapping on the spin properties of elongated structures. The magnetic parameters, determined through spin-Hamiltonian simulation of the steady-state ODMR spectra, reflect anisotropy associated with carrier trapping at the seed/rod interface. These observations unveiled changes in the carriers' g-factors and spin-exchange coupling constants as well as extension of radiative and spin-lattice relaxation times due to magnetic coupling between interface carriers and neighboring Mn2+ ions. Overall, this work highlights that the spin degrees of freedom in seeded nanorods are governed by interfacial trapping and can be further manipulated by magnetic doping. These results provide insights into anisotropic nanostructure spin properties relevant to future spin-based technologies.
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Affiliation(s)
- Joanna Dehnel
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Yahel Barak
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Itay Meir
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Adam K Budniak
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Anjani P Nagvenkar
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Daniel R Gamelin
- Department of Chemistry and the Molecular Engineering Materials Center, University of Washington, Box 351700, Seattle, Washington 98195-1700, United States
| | - Efrat Lifshitz
- Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
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7
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Shornikova EV, Yakovlev DR, Tolmachev DO, Ivanov VY, Kalitukha IV, Sapega VF, Kudlacik D, Kusrayev YG, Golovatenko AA, Shendre S, Delikanli S, Demir HV, Bayer M. Magneto-Optics of Excitons Interacting with Magnetic Ions in CdSe/CdMnS Colloidal Nanoplatelets. ACS NANO 2020; 14:9032-9041. [PMID: 32585089 DOI: 10.1021/acsnano.0c04048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Excitons in diluted magnetic semiconductors represent excellent probes for studying the magnetic properties of these materials. Various magneto-optical effects, which depend sensitively on the exchange interaction of the excitons with the localized spins of the magnetic ions can be used for probing. Here, we study core/shell CdSe/(Cd,Mn)S colloidal nanoplatelets hosting diluted magnetic semiconductor layers. The inclusion of the magnetic Mn2+ ions is evidenced by three magneto-optical techniques using high magnetic fields up to 15 T: polarized photoluminescence, optically detected magnetic resonance, and spin-flip Raman scattering. We show that the holes in the excitons play the dominant role in exchange interaction with magnetic ions. We suggest and test an approach for evaluation of the Mn2+ concentration based on the spin-lattice relaxation dynamics of the Mn2+ spin system.
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Affiliation(s)
- Elena V Shornikova
- Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, Germany
| | - Dmitri R Yakovlev
- Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, Germany
- Ioffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia
| | - Danil O Tolmachev
- Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, Germany
- Ioffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia
| | - Vitalii Yu Ivanov
- Institute of Physics, Polish Academy of Sciences, PL-02-668 Warsaw, Poland
| | - Ina V Kalitukha
- Ioffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia
| | - Victor F Sapega
- Ioffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia
| | - Dennis Kudlacik
- Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, Germany
| | - Yuri G Kusrayev
- Ioffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia
| | | | - Sushant Shendre
- LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, Nanyang Technological University, 639798 Singapore
| | - Savas Delikanli
- LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, Nanyang Technological University, 639798 Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology, Bilkent University, 06800 Ankara, Turkey
| | - Hilmi Volkan Demir
- LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, Nanyang Technological University, 639798 Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM - Institute of Materials Science and Nanotechnology, Bilkent University, 06800 Ankara, Turkey
| | - Manfred Bayer
- Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, Germany
- Ioffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia
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Fainblat R, Delikanli S, Spee L, Czerny T, Isik F, Sharma VK, Demir HV, Bacher G. Impurity incorporation and exchange interactions in Co2+-doped CdSe/CdS core/shell nanoplatelets. J Chem Phys 2019; 151:224708. [DOI: 10.1063/1.5129391] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Rachel Fainblat
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057, Germany
| | - Savas Delikanli
- Luminous! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, School of Materials Sciences and Engineering, Nanyang Technological University, 639798, Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM-Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Turkey
| | - Leon Spee
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057, Germany
| | - Tamara Czerny
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057, Germany
| | - Furkan Isik
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM-Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Turkey
| | - Vijay Kumar Sharma
- Luminous! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, School of Materials Sciences and Engineering, Nanyang Technological University, 639798, Singapore
| | - Hilmi Volkan Demir
- Luminous! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, School of Materials Sciences and Engineering, Nanyang Technological University, 639798, Singapore
- Department of Electrical and Electronics Engineering, Department of Physics, UNAM-Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Turkey
| | - Gerd Bacher
- Werkstoffe der Elektrotechnik and CENIDE, University of Duisburg-Essen, Bismarckstr. 81, Duisburg 47057, Germany
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