论文标题
对机械,光电,热物理和晶格的动力学特性的第一原理见解
First-principles insights into the mechanical, optoelectronic, thermophysical, and lattice dynamical properties of binary topological semimetal BaGa2
论文作者
论文摘要
在本研究中,我们研究了结构特性,电子带分散,弹性常数,声学行为,声子谱,光学特性,以及使用基于基于密度的功能(DFT)的形式主义的第一个原理计算的二进制拓扑半学分BAGA2的许多热物理参数。带有旋转轨道耦合的状态计算的电子带结构和密度揭示了具有清晰拓扑特征的半金属性质。计算该化合物的最小导电性和各向异性。弹性常数,声子分散计算表明,所研究的化合物在机械上和动态稳定。对弹性常数和模量的全面研究表明,Baga2具有相当各向同性的机械性能,合理的可加工性,低的DEBYE温度和熔点。 BAG2中的化学键通过状态的电子能量密度,电子密度分布,弹性特性和Mulliken键种群分析来解释。该化合物具有离子和共价键。反射率光谱相对于可见到中脉中区域的入射电场极化而显示出强的各向异性。高反射率在宽光谱范围内使Baga2适合作为反射材料。 Baga2也是紫外线辐射的有效吸收剂。此外,折射率在可见范围内的折射率很高。所有依赖能量的光学参数均显示金属特征,并且完全符合状态计算的基本批量电子密度。这项研究中提出的大多数结果都是新颖的,应作为未来研究的有用参考。
In the present study we have investigated the structural properties, electronic band dispersion, elastic constants, acoustic behavior, phonon spectrum, optical properties, and a number of thermophysical parameters of binary topological semimetal BaGa2 in details via first-principles calculations using the density functional theory (DFT) based formalisms. The electronic band structure and density of states calculations with spin orbit coupling reveal semimetallic nature with clear topological signature. The minimum thermal conductivities and anisotropies of the compound are calculated. The elastic constants, phonon dispersion calculations show that the compound under study is both mechanically and dynamically stable. Comprehensive study of elastic constants and moduli shows that BaGa2 possesses fairly isotropic mechanical properties, reasonably good machinability, low Debye temperature and melting point. The chemical bonding in BaG2 is interpreted via the electronic energy density of states, electron density distribution, elastic properties and Mulliken bond population analysis. The compound possesses both ionic and covalent bondings. The reflectivity spectra show strong anisotropy with respect to polarization of the incident electric field in the visible to mid-ultraviolet regions. High reflectivity over wide spectral range makes BaGa2 suitable as a reflecting material. BaGa2 is also an efficient absorber of ultraviolet radiation. Furthermore, the refractive index is quite high in the infrared to visible range. All the energy dependent optical parameters show metallic features and are in complete accord with the underlying bulk electronic density of states calculations. Most of the results presented in this study are novel and should serve as useful reference for future study.