The Experts below are selected from a list of 19170 Experts worldwide ranked by ideXlab platform
Zexing Cao - One of the best experts on this subject based on the ideXlab platform.
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si c c 4 based single crystalline semiconductor diamond like superlight and superflexible wide Bandgap Material for the uv photoconductive device
ACS Applied Materials & Interfaces, 2016Co-Authors: Xinrui Cao, Zexing CaoAbstract:A wide-Bandgap SiC4 semiconductor with low density and high elasticity has been designed and characterized by ab initio molecular dynamics simulations and first-principles calculations. The through-space conjugation among the d orbitals of Si and the π* orbitals of ethynyl moieties can remarkably enhance the photoconductivity. This new-type superlight and superflexible semiconductor is predicted to have unique electronic, optical, and mechanical properties, and it is a quite promising Material for the high-performance UV optoelectronic devices suitable for various practical demands in a complex environment.
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Si(C≡C)4-Based Single-Crystalline Semiconductor: Diamond-like Superlight and Superflexible Wide-Bandgap Material for the UV Photoconductive Device.
ACS Applied Materials & Interfaces, 2016Co-Authors: Ming-jun Sun, Xinrui Cao, Zexing CaoAbstract:A wide-Bandgap SiC4 semiconductor with low density and high elasticity has been designed and characterized by ab initio molecular dynamics simulations and first-principles calculations. The through-space conjugation among the d orbitals of Si and the π* orbitals of ethynyl moieties can remarkably enhance the photoconductivity. This new-type superlight and superflexible semiconductor is predicted to have unique electronic, optical, and mechanical properties, and it is a quite promising Material for the high-performance UV optoelectronic devices suitable for various practical demands in a complex environment.
Guillaume Cassabois - One of the best experts on this subject based on the ideXlab platform.
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Hexagonal boron nitride: an indirect Bandgap semiconductor with unique opto-electronic properties
2017Co-Authors: Guillaume CassaboisAbstract:I will discuss our recent studies showing that the optical response in hBN displays prominent evidence for phonon-assisted optical transitions, with a very unusual phenomenology. By two-photon spectroscopy, we demonstrated that the intrinsic optical properties at the band edge are characteristic of an indirect Bandgap Material. Polarization-resolved experiments with a detection from the sample edge allowed us to show that the phonon symmetries can be traced back in the optical response. I will further highlight the unique properties of this Material where the optical response is tailored by the phonon group velocities in the middle of the Brillouin zone. I will finally present optical characterization results of the promising high-temperature MBE growth of hBN.
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Hexagonal boron nitride: an indirect Bandgap semiconductor with unique opto-electronic properties
2017Co-Authors: Guillaume CassaboisAbstract:I will discuss our recent studies showing that the optical response in hBN displays prominent evidence for phonon-assisted optical transitions, with a very unusual phenomenology. By two-photon spectroscopy, we demonstrated that the intrinsic optical properties at the band edge are characteristic of an indirect Bandgap Material. Polarization-resolved experiments with a detection from the sample edge allowed us to show that the phonon symmetries can be traced back in the optical response. I will further highlight the unique properties of this Material where the optical response is tailored by the phonon group velocities in the middle of the Brillouin zone. I will finally present optical characterization results of the promising high-temperature MBE growth of hBN, in collaboration with Nottingham University.
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Phonon-assisted optical response in hexagonal boron nitride
2017Co-Authors: Guillaume CassaboisAbstract:I will discuss our recent studies showing that the optical response in hBN displays prominent evidence for phonon-assisted optical transitions. First of all, by two-photon spectroscopy, we have demonstrated that the intrinsic optical properties at the band edge are characteristic of an indirect Bandgap Material. I will further discuss our experimental evidence that transverse optical phonons at the K point of the Brillouin zone assist inter-K valley scattering in hexagonal boron nitride, thanks to the presence of a density of final electronic states coming from extended stacking faults. Finally, I will present our measurements of the vibronic spectrum in a point defect in hBN, displaying a remarkable mapping with the phonon density of states, and in particular a suppression of the phonon-assisted recombination signal at the phonon gap energy. I will discuss our recent studies showing that the optical response in hBN displays prominent evidence for phonon-assisted optical transitions. First of all, by two-photon spectroscopy, we have demonstrated that the intrinsic optical properties at the band edge are characteristic of an indirect Bandgap Material. I will further discuss our experimental evidence that transverse optical phonons at the K point of the Brillouin zone assist inter-K valley scattering in hexagonal boron nitride, thanks to the presence of a density of final electronic states coming from extended stacking faults. Finally, I will present our measurements of the vibronic spectrum in a point defect in hBN, displaying a remarkable mapping with the phonon density of states, and in particular a suppression of the phonon-assisted recombination signal at the phonon gap energy.
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Indirect excitons and electron-phonon interaction in hexagonal boron nitride
2016Co-Authors: Guillaume CassaboisAbstract:In this paper, we discuss our recent experiments by two-photon spectroscopy demonstrating that hBN is an indirect Bandgap Material. We will show that the optical properties of hBN are profoundly determined by phonon-assisted transitions involving either virtual or real excitonic states. We will present our measurements of the exciton binding energy by two-photon excitation, leading to the estimation of 6.08 eV for the single-particle Bandgap in hBN. We will also discuss our experimental evidence that transverse optical phonons at the K point of the Brillouin zone assist inter-K valley scattering in hexagonal boron nitride.
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Indirect excitons and electron-phonon interaction in hexagonal boron nitride
2016Co-Authors: Guillaume CassaboisAbstract:I will discuss our recent experiments by two-photon spectroscopy demonstrating that hBN is an indirect Bandgap Material. I will show that the optical properties of hBN are profoundly determined by phonon-assisted transitions involving either virtual or real excitonic states. I will present our measurements of the exciton binding energy by two-photon excitation, leading to the estimation of 6.08 eV for the single-particle Bandgap in hBN. I will also discuss our experimental evidence that transverse optical phonons at the K point of the Brillouin zone assist inter-K valley scattering in hexagonal boron nitride.
J S Williams - One of the best experts on this subject based on the ideXlab platform.
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synthesis of ge1 xsnx alloys by ion implantation and pulsed laser melting towards a group iv direct Bandgap Material
Journal of Applied Physics, 2016Co-Authors: Tuan T. Tran, David Pastor, Hemi H. Gandhi, Lachlan A. Smillie, Austin J. Akey, Michael J. Aziz, J S WilliamsAbstract:Synthesis of Ge1−xSnx alloys by ion implantation and pulsed laser melting: Towards a group IV direct Bandgap Material
R Asomoza - One of the best experts on this subject based on the ideXlab platform.
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plasma cvd deposited p type silicon oxide wide Bandgap Material for solar cells
Solar Energy Materials and Solar Cells, 1998Co-Authors: Yasuhiro Matsumoto, F Melendez, R AsomozaAbstract:Abstract The short-circuit current density is an important parameter to improve the conversion efficiency of solar cells. Solar cells with heterojunction structures employing a wide-Bandgap window-layers are nowadays common to achieve greater photogenerated current. Plasma CVD deposited a-SiO x : H (Hydrogenated amorphous silicon oxide) has been widely used as an insulator and for surface passivation in electronic device manufacturing, however, there is little knowledge about doped Materials. We have prepared a-SiO x : H films using silane (SiH 4 ) and oxygen (O 2 ) as reactive gases in a capacitively-coupled single-chamber plasma CVD system. Diborane (B 2 H 6 ) was introduced as a doping gas to obtain p-type conduction silicon oxide. In this work we report properties of the prepared Materials at different substrate temperatures, plasma power and doping concentrations. The optical Bandgap increases with oxygen-to-silane-gas-flow ratio, while the electrical conductivity decreases. The optical Bandgap changes easily as a function of gas-source ratio from 1.3 to 2.0 eV. The deposition rate varies from 10 to 22 nm/min, depending mostly on the plasma excitation power. As a first approach, hydrogenated amorphous silicon solar cells have been fabricated using p-type a-SiO x : H with around 1.85 eV optical Bandgap and conductivity greater than 10 −7 Scm. The measured current–voltage characteristics of the solar cells under the artificial light of 100 mW/cm 2 are V oc =0.84 V, J sc =14.66 mA/cm 2 with a conversion efficiency of 6.95%.
Xinrui Cao - One of the best experts on this subject based on the ideXlab platform.
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si c c 4 based single crystalline semiconductor diamond like superlight and superflexible wide Bandgap Material for the uv photoconductive device
ACS Applied Materials & Interfaces, 2016Co-Authors: Xinrui Cao, Zexing CaoAbstract:A wide-Bandgap SiC4 semiconductor with low density and high elasticity has been designed and characterized by ab initio molecular dynamics simulations and first-principles calculations. The through-space conjugation among the d orbitals of Si and the π* orbitals of ethynyl moieties can remarkably enhance the photoconductivity. This new-type superlight and superflexible semiconductor is predicted to have unique electronic, optical, and mechanical properties, and it is a quite promising Material for the high-performance UV optoelectronic devices suitable for various practical demands in a complex environment.
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Si(C≡C)4-Based Single-Crystalline Semiconductor: Diamond-like Superlight and Superflexible Wide-Bandgap Material for the UV Photoconductive Device.
ACS Applied Materials & Interfaces, 2016Co-Authors: Ming-jun Sun, Xinrui Cao, Zexing CaoAbstract:A wide-Bandgap SiC4 semiconductor with low density and high elasticity has been designed and characterized by ab initio molecular dynamics simulations and first-principles calculations. The through-space conjugation among the d orbitals of Si and the π* orbitals of ethynyl moieties can remarkably enhance the photoconductivity. This new-type superlight and superflexible semiconductor is predicted to have unique electronic, optical, and mechanical properties, and it is a quite promising Material for the high-performance UV optoelectronic devices suitable for various practical demands in a complex environment.
