Article
Physics, Multidisciplinary
Sandeep Arora, Dharamvir Singh Ahlawat, Dharmbir Singh
Summary: In this study, different DFT methods (LDA, PBE, WC, PBEsol, and SCAN) were used to calculate the electronic properties of semiconducting materials belonging to III-V and II-VI groups. The results showed that LDA underestimated while PBE overestimated the experimental lattice constants for these materials. WC, PBEsol, and SCAN functionals provided better agreement with experimental results compared to optB88vdW functional.
PRAMANA-JOURNAL OF PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Chuan-Zhen Zhao, Yu-Li Wang
Summary: In this study, first-principles calculations were used to investigate the lattice constant and bandgap energy of S-rich ZnOxS1-x alloys, revealing a small negative bowing coefficient for the lattice constant in the S-rich range and bandgap reduction due to the coupling interaction between O-2s and Zn-4s states.
JOURNAL OF ELECTRONIC MATERIALS
(2022)
Article
Physics, Condensed Matter
V. N. Jafarova, G. S. Orudzhev
Summary: This study investigates the structural and electronic properties of bulk ZnO using density functional theory. By employing different methods, parameters such as band structure and density of states are calculated, showing agreement with experimental results.
SOLID STATE COMMUNICATIONS
(2021)
Article
Materials Science, Characterization & Testing
Dustin T. Clelland, Ethan K. Nickerson, Daniel R. Merkel
Summary: This article presents a method for directly measuring the bulk modulus of rubber using a piston-cylinder type apparatus. The apparatus reliably transfers load to the water inside the vessel and allows for accurate and continuous measurement of volumetric displacement. The method involves applying load to a piston-cylinder containing the rubber sample and water, recording load and piston travel, and mathematically converting the data to calculate bulk modulus. A control test using a brass or stainless steel plug is performed to isolate system compliance. The validity of the method is confirmed using the known bulk modulus of water, and the bulk moduli of two rubber samples are evaluated. The article also discusses the limitations of the device.
Article
Chemistry, Physical
Bushra Anam, Nicola Gaston
Summary: The research predicted various possible two-dimensional allotropes of beta-Ga2O3, and found that one or two of them are stable by analyzing their structural and dynamical stability. These 2D semiconducting oxides with larger indirect band gaps provide a new avenue for developing nano-devices with enhanced electronic properties.
Article
Chemistry, Physical
Shenggui Ma, Xue Ye, Xia Jiang, Wanglai Cen, Wenju Jiang, Hualin Wang
Summary: A spin-polarized DFT + U method was used to study the structural, mechanical, lattice dynamical, and thermodynamic properties of alpha-, beta-, gamma- and delta-MnO2. All four kinds of MnO2 were found to be mechanically and dynamically stable, with alpha- and beta-MnO2 being ductile, and gamma-MnO2 being brittle. The phonon vibrational frequencies were analyzed in detail and compared with experimental values to resolve uncertainties in assignment.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Physics, Multidisciplinary
Marios Zacharias, Helene Seiler, Fabio Caruso, Daniela Zahn, Feliciano Giustino, Pantelis C. Kelires, Ralph Ernstorfer
Summary: Inelastic scattering experiments are crucial for mapping fundamental excitations of solids, with a particular focus on the role of multiphonon processes for phonon excitations. A new first-principles methodology has been developed to calculate the all-phonon quantum mechanical structure factor of solids, demonstrating the significance of multiphonon processes in the scattering patterns of black phosphorus. This approach represents a significant step towards interpreting static and time-resolved electron, x-ray, and neutron inelastic scattering data.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Applied
Qiong Xia, Zhiyuan Xu, Lei Hu, Yushen Liu, Guoying Gao
Summary: It is found that the Coulomb interaction can effectively eliminate the imaginary frequency of the phonon spectrum in TlCuSe, as demonstrated by density functional theory (DFT) and phonon Boltzmann transport theory. The competition between increased phonon group velocity and decreased phonon relaxation time leads to a decrease in lattice thermal conductivity, especially in the form of monolayers.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Saro San, Yang Tong, Hongbin Bei, Boopathy Kombaiah, Yanwen Zhang, Wai-Yim Ching
Summary: A comparative study of high entropy alloys using ab initio calculations reveals intricate interdependence among electronic structure, interatomic bonding, partial charge distribution, and mechanical properties. The novel parameter of total bond order density (TBOD) is used to interpret the properties, with highest TBOD found in Cantor alloy NiFeCoCrMn. Experimental validation shows lattice distortions in NiFeCoCrMn and NiFeCoCrPd based on atomic radii variations. Modeling of Cu and Pd clustering in the supercell demonstrates lower total energy, consistent with observed enhancements in Cu and Pd-induced concentration wave in HEAs.
MATERIALS & DESIGN
(2021)
Article
Materials Science, Multidisciplinary
Farzad Mahfouzi, Nicholas Kioussis
Summary: The study introduces a Green's function approach for calculating DMIs, which is more efficient and accurate than commonly used supercell and generalized Bloch-based methods. Calculations on a (111) Co/Pt bilayer show that DMI is influenced by thickness. Additionally, the study demonstrates that DMI can be significantly modulated by strains.
Article
Materials Science, Multidisciplinary
Ming-Xu Wang, Hong Zhu, Gong-Ji Yang, Ke Liu, Jin-Fu Li, Ling-Ti Kong
Summary: The study revealed that the strengthening effects of alloying elements in Ni are influenced by their positions on the periodic table, with elements at the ends of each period showing higher strengthening abilities than those in the middle. For elements in the 5th and 6th period, lattice misfit was found to dominate the strengthening effect. Experimental solubilities were used to evaluate the strengthening potentials of these elements.
MATERIALS & DESIGN
(2021)
Article
Materials Science, Multidisciplinary
Ali H. Bashal, Tokeer Ahmad, Umar Farooq, Talat Habeeb, Hanaa AL-Refai, Mohammed Khalafalla
Summary: In this study, undoped and Zn and Co incorporated bentonite samples were successfully synthesized and characterized. The incorporation of metal ions was found to improve the dielectric properties of bentonite samples, especially at high temperatures.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
Shaho M. Rasul, Dlear R. Saber, Shujahadeen B. Aziz
Summary: Doping transition metal Palladium (Pd) into titanium dioxide (TiO2) can greatly improve its electronic structure and optical properties, leading to enhanced absorption in the visible light region.
RESULTS IN PHYSICS
(2022)
Article
Instruments & Instrumentation
Chuan-Zhen Zhao, Hui-Jing Hu, Kai-Yue Zheng, Fei Wang
Summary: The structure and electronic properties of As-rich InBixAs1-x were investigated using the generalized gradient approximation (GGA) plus Hubbard U parameter method. It was found that the lattice constant can be better described by the standard bowing equation rather than the linear equation. Incorporating bismuth atoms in InAs was observed to significantly reduce the bandgap energy by increasing the valence band maximum (VBM) and decreasing the conduction band minimum (CBM). The combination of the modified valence band anticrossing (MVBAC) model and a linear equation was found to accurately estimate the bandgap energy.
INFRARED PHYSICS & TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Hamza A. H. Mohammed, G. M. Dongho-Nguimdo, Daniel P. Joubert
Summary: First-principles calculations were used to study the properties of different α-PtO2 structures, revealing that the monolayer is harder than the bulk, with an increased band gap, and superior thermoelectric performance.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2021)