Article
Nanoscience & Nanotechnology
Joseph Sink, Craig Pryor
Summary: Suitable tight-binding models for wurtzite III-V (non-nitride) and group-V materials are currently lacking in literature. Existing models for cubic-zincblende semiconductors result in inaccurate band structures for hexagonal polytypes. Wurtzite parameters are useful for modeling nanowires condensing into either wurtzite or zincblende phases. We have developed spds tight-binding parameters for wurtzite crystal phase in non-nitride III-V and group V semiconductors, which, when combined with zincblende parameters, allow for modeling heterostructures with both crystal phases.
Article
Materials Science, Multidisciplinary
L. Krauss-Kodytek, W. -R. Hannes, T. Meier, C. Ruppert, M. Betz
Summary: The study investigates the nondegenerate two-photon absorption coefficient beta(omega(1), omega(2)) in the semiconductor ZnSe, showing a substantial increase in absorption strength with higher omega(1)/omega(2) ratio. Different crystallographic orientations and polarization configurations are considered, with theoretical analysis aligning well with experimental results.
Article
Materials Science, Multidisciplinary
Sergey S. Krishtopenko, Frederic Teppe
Summary: Using an elegant model involving only Gamma(6c) and Gamma(8v) bands, the authors found that Kane fermions are two nested Dirac particles. Studying their behavior in crossed electric and magnetic fields, it was observed that Kane fermions decay into two independent Dirac particles with increase of the electric field.
Article
Chemistry, Multidisciplinary
Xilong Liang, Chengbing Qin, Yan Gao, Shuangping Han, Guofeng Zhang, Ruiyun Chen, Jianyong Hu, Liantuan Xiao, Suotang Jia
Summary: The study found that the spin-orbit coupling of monolayer MoS2 can be reversibly engineered by laser irradiation under controlled gas environments, where the spin-orbit splitting has been effectively regulated within 140 meV to 200 meV, and the photoluminescence intensity of the B exciton can be reversibly manipulated over 2 orders of magnitude.
Article
Physics, Applied
Hitoshi Takane, Itsuhiro Kakeya, Hirokazu Izumi, Takeru Wakamatsu, Yuki Isobe, Kentaro Kaneko, Katsuhisa Tanaka
Summary: This study reports the low-temperature electron transport properties of r-GexSn1-xO2 thin films and finds that Efros-Shklovskii variable-range hopping dominates at lower temperatures, while Mott variable-range hopping and thermally activated band conduction occur at higher temperatures.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Engineering, Geological
Yuxuan Wen, Yida Zhang
Summary: This study uses the discrete element method to conduct a series of tests and finds a tight correlation between the void ratio and the fabric tensor of granular soils. By plotting the void ratio data against the first two invariants of the fabric tensor, a unique surface is obtained. The robustness of this relation is confirmed through testing samples with different initial void ratios under complex loading paths.
Article
Mechanics
Michael Grog, Julian Dietzsch, Francesca Concas
Summary: Liquid crystalline elastomers (LCE) are soft materials that can undergo large deformations due to temperature changes and ultraviolet irradiation. This study presents a continuum model and a variational-based reorientation finite element formulation for numerical simulations of LCE materials. The dissipative reorientation of mesogens is described using an orientation vector field and micropolar rotational degrees of freedom.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2023)
Article
Chemistry, Physical
Marc H. Garner, Clemence Corminboeuf
Summary: Electrohelicity arises in molecules when their symmetry is reduced and helical frontier molecular orbitals (MOs) appear, leading to optical activity. However, the fundamental connection between electrohelicity and optical activity is molecule-dependent. By studying the origin of the electric and magnetic transition dipole moments of pi-pi* transitions, we found that the helical character of MOs drives the optical activity in certain molecules, but there is no relation between the chiroptical response and the helical pi-MOs of other molecules. Insight into the helical nature of electronic transitions can enhance the chiroptical response.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Sajid Rauf, Muhammad Bilal Hanif, Faiz Wali, Zuhra Tayyab, Bin Zhu, Naveed Mushtaq, Yatao Yang, Kashif Khan, Peter D. Lund, Martin Motola, Wei Xu
Summary: Extending ionic conductivity is essential for high-electrochemical performance in fuel cell technology. In this study, semiconductor-oxide materials were introduced to enhance ionic conduction, and heterostructure formation by modulating energy bands was used as an electrolyte in fuel cell devices. The SFT-SnO2 heterojunction exhibited excellent ionic conductivity, high power-output, and durability, indicating its potential for semiconductor-based fuel cell technology.
ENERGY & ENVIRONMENTAL MATERIALS
(2023)
Article
Physics, Applied
Ke Zhao, Huiwen Xiang, Yingru Cui, Rui Zhu, Chengyan Liu, Yu Jia
Summary: This study investigates the use of Li-based selenized CZTS surface treatment to improve the open-circuit voltage deficit in thin film solar cells, effectively suppressing carrier nonradiative recombination and facilitating electron transmission.
APPLIED PHYSICS LETTERS
(2021)
Article
Nanoscience & Nanotechnology
Mehmet Aras, Sumeyra Guler-Kilic, Cetin Kilic
Summary: The magnetic anisotropy of single semiconductor nanowires (ZnO and GaN) with incorporation of transition metal and heavy metal adatoms is studied by density-functional supercell calculations. Deposition of Bi enhances the magnetic anisotropy energy, while deposition of Au and Pt leads to significant variations in other magnetic properties. An analysis within a band description reveals that the coexistence of Bi adatom and a surface dopant with large spin moment activates a mechanism promoting giant magnetic anisotropy.
Article
Computer Science, Interdisciplinary Applications
D. Liao, Z. X. Yang, T. T. Xu
Summary: This paper introduces a sand mechanics model with only ten parameters, which is simple for calibration and applicable in practical engineering designs. The model's performance and ability to simulate anisotropic behavior are demonstrated through various tests, showcasing its robustness.
COMPUTERS AND GEOTECHNICS
(2021)
Article
Materials Science, Multidisciplinary
Tuan V. Vu, A. A. Lavrentyev, B. V. Gabrelian, Khang D. Pham, O. V. Parasyuk, N. M. Denysyuk, O. Y. Khyzhun
Summary: The electronic structure and optical properties of cesium lead chloride (CsPbCl3) were studied experimentally and theoretically in this research. X-ray photoelectron spectroscopy was used to measure core-level electron binding energies and valence band electronic states distribution of CsPbCl3. Various approaches were employed to achieve agreement between XPS spectra and density of states curve, with modified Becke-Johnson potential and treatment of Hubbard parameter U and spin-orbit coupling showing fair agreement. This study explored partial density of states curves, energy band dispersion, and principal optical constants of CsPbCl3 using these techniques.
MATERIALS CHEMISTRY AND PHYSICS
(2021)
Article
Physics, Multidisciplinary
Zhenglu Li, Meng Wu, Yang-Hao Chan, Steven G. Louie
Summary: Through ab initio calculations and GW perturbation theory, we found that correlation-enhanced electron-phonon interaction in cuprates leads to the energy-momentum dispersion kinks observed in the spectra, explaining the observations and providing new experimental insights. Our results reveal that the electron density of states is the predominant factor in determining the kink size, demonstrating the multiband nature of cuprates.
PHYSICAL REVIEW LETTERS
(2021)
Article
Nanoscience & Nanotechnology
Taras Parashchuk, Rafal Knura, Oleksandr Cherniushok, Krzysztof T. Wojciechowski
Summary: This study systematically investigates the microstructure and thermoelectric properties of Cl-doped Bi2Te3-xSex alloys and finds that Cl atoms act as electron donors to regulate the carrier concentration and effectively suppress minority carrier transport in Bi2Te3-xSex alloys. By manipulating the polarity of Bi-(Te/Se)1 and Bi-(Te/Se)2 bonds as well as the lone-pair (Te/Se) interactions, a significant reduction of lattice thermal conductivity in both pressing directions is achieved. As a result, a maximum ZT value of 1.0 is obtained at 473 K in the Bi2Te2.385Se0.6Cl0.015 sample.
ACS APPLIED MATERIALS & INTERFACES
(2022)