The Experts below are selected from a list of 123 Experts worldwide ranked by ideXlab platform
Tzer-en Nee - One of the best experts on this subject based on the ideXlab platform.
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Effect of column III vacancy on arsenic precipitation in low-temperature grown III–V arsenides
Applied Physics Letters, 1998Co-Authors: Mao-nan Chang, J.-w. Pan, J.-i. Chyi, K. C. Hsieh, Tzer-en NeeAbstract:Separately grown p-type, intrinsic, and n-type GaAs at low temperatures as well as a combined p-i-n structure have been used to study the formation of As precipitates upon annealing at 800 °C. For the separate structures, least precipitates have been noticed in the n-type material. In contrast, the highest density of precipitates appears in the n region for the p-i-n structure. In addition, an obvious band depleted of precipitates, exists in the intrinsic region near the n-i interface. A general vacancy model, including Fermi level effect and Crystal Bonding strength (thermodynamic factor), has been developed to explain the current results as well as to predict As precipitation in various low temperature grown III–V heterostructures.
Warren E. Pickett - One of the best experts on this subject based on the ideXlab platform.
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Role of Crystal symmetry in the magnetic instabilities of β-YbAlB 4 and α-YbAlB 4
Physical Review B, 2010Co-Authors: D. A. Tompsett, Zhiping Yin, G. G. Lonzarich, Warren E. PickettAbstract:Density functional theory methods are applied to investigate the properties of the new superconductor $\beta$-YbAlB$_4$ and its polymorph $\alpha$-YbAlB$_4$. We utilize the generalized gradient approximation + Hubbard U (GGA+U) approach with spin-orbit(SO) coupling to approximate the effects of the strong correlations due to the open $4f$ shell of Yb. We examine closely the differences in Crystal Bonding and symmetry of $\beta$-YbAlB$_4$ and $\alpha$-YbAlB$_4$. The in-plane Bonding structure amongst the dominant itinerant electrons in the boron sheets is shown to differ significantly. Our calculations indicate that, in both polymorphs, the localized 4$f$ electrons hybridize strongly with the conduction sea when compared to the related materials YbRh$_{2}$Si$_{2}$ and YbB$_{2}$. Comparing $\beta$-YbAlB$_4$ to the electronic structure of related Crystal structures indicates a key role of the 7-member boron coordination of the Yb ion in $\beta$-YbAlB$_4$ in producing its enhanced Kondo scale and superconductivity. The Kondo scale is shown to depend strongly on the angle between the B neighbors and the Yb ion, relative to the $x-y$ plane, which relates some of the physical behavior to structural characteristics.
Mao-nan Chang - One of the best experts on this subject based on the ideXlab platform.
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Effect of column III vacancy on arsenic precipitation in low-temperature grown III–V arsenides
Applied Physics Letters, 1998Co-Authors: Mao-nan Chang, J.-w. Pan, J.-i. Chyi, K. C. Hsieh, Tzer-en NeeAbstract:Separately grown p-type, intrinsic, and n-type GaAs at low temperatures as well as a combined p-i-n structure have been used to study the formation of As precipitates upon annealing at 800 °C. For the separate structures, least precipitates have been noticed in the n-type material. In contrast, the highest density of precipitates appears in the n region for the p-i-n structure. In addition, an obvious band depleted of precipitates, exists in the intrinsic region near the n-i interface. A general vacancy model, including Fermi level effect and Crystal Bonding strength (thermodynamic factor), has been developed to explain the current results as well as to predict As precipitation in various low temperature grown III–V heterostructures.
D. A. Tompsett - One of the best experts on this subject based on the ideXlab platform.
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Role of Crystal symmetry in the magnetic instabilities of β-YbAlB 4 and α-YbAlB 4
Physical Review B, 2010Co-Authors: D. A. Tompsett, Zhiping Yin, G. G. Lonzarich, Warren E. PickettAbstract:Density functional theory methods are applied to investigate the properties of the new superconductor $\beta$-YbAlB$_4$ and its polymorph $\alpha$-YbAlB$_4$. We utilize the generalized gradient approximation + Hubbard U (GGA+U) approach with spin-orbit(SO) coupling to approximate the effects of the strong correlations due to the open $4f$ shell of Yb. We examine closely the differences in Crystal Bonding and symmetry of $\beta$-YbAlB$_4$ and $\alpha$-YbAlB$_4$. The in-plane Bonding structure amongst the dominant itinerant electrons in the boron sheets is shown to differ significantly. Our calculations indicate that, in both polymorphs, the localized 4$f$ electrons hybridize strongly with the conduction sea when compared to the related materials YbRh$_{2}$Si$_{2}$ and YbB$_{2}$. Comparing $\beta$-YbAlB$_4$ to the electronic structure of related Crystal structures indicates a key role of the 7-member boron coordination of the Yb ion in $\beta$-YbAlB$_4$ in producing its enhanced Kondo scale and superconductivity. The Kondo scale is shown to depend strongly on the angle between the B neighbors and the Yb ion, relative to the $x-y$ plane, which relates some of the physical behavior to structural characteristics.
Yusuke Takayama - One of the best experts on this subject based on the ideXlab platform.
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polarization dependence of two photon absorption coefficient and nonlinear susceptibility tensor in inp
Physica Status Solidi (c), 2011Co-Authors: Toshio Matsusue, Hiroyuki Bando, Shoichi Fujita, Yusuke TakayamaAbstract:Two-photon absorption (TPA) effect in (001) InP is investigated using fs laser. Its dependences on wavelength and polarization are clarified by single and double beam methods with linearly polarized lights. Characteristic features are revealed and discussed with scaling law, Crystal Bonding and mutual relation of polarizations for double beams. The results are successfully analyzed on the basis of the third-order susceptibility tensor for comprehensive understanding of TPA effect at any polarization geometry. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
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Polarization dependence of two‐photon absorption coefficient and nonlinear susceptibility tensor in InP
physica status solidi (c), 2011Co-Authors: Toshio Matsusue, Hiroyuki Bando, Shoichi Fujita, Yusuke TakayamaAbstract:Two-photon absorption (TPA) effect in (001) InP is investigated using fs laser. Its dependences on wavelength and polarization are clarified by single and double beam methods with linearly polarized lights. Characteristic features are revealed and discussed with scaling law, Crystal Bonding and mutual relation of polarizations for double beams. The results are successfully analyzed on the basis of the third-order susceptibility tensor for comprehensive understanding of TPA effect at any polarization geometry. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)