Khandy Saveer Ahmad, Gupta Dinesh C
Condensed Matter Theory Group, School of Studies in Physics, Jiwaji University, Gwalior, 474011, India.
Sci Rep. 2022 Nov 16;12(1):19690. doi: 10.1038/s41598-022-22070-x.
Since the unexpected accelerated discovery of half-metallic perovskites is continuously on the rise both from basic sciences and application-oriented sides. Herein, for the first time in this carried research work, we significantly delivered a detailed analysis on one of experimentally synthesized perovskite structure BaErNbO and in related to BaTmNbO within the realm of unified density functional theory. Initially, the structural stability of two molecular perovskite structures were critically established interms of their total ground state and cohesive energies by the expendition of Brich Murnaghan equation of state. Also, the tolerance factor (τ) oversees the cubic structural stability without possessing any geometrical strains. More likely, the density functional perturbation theory (DFPT) has been calibrated to perceive the dynamical context of these layered structures. Also, from the understandings of second order elastic and mechanical parameters adresses their suitable ductile characteristics. The quantum mechanical refinement of their intrinsic electronic structures were systematically tuned by the exploitation of Generalised gradient approximation (GGA), on-site Hubbard scheme (GGA + U) selected to the strongly correlated electrons of particular angular momentum and modified Becke-Johnson (mBJ) potential. Moreover, the two-dimensional representation of asymmetric density of states (DOS) pinned around the Fermi-level (E) and the interpretation linked to their corresponding spin-polarised band structures signatures the well-known half-metallic nature. Subsequently, the transport properties especially the value of figure of merit (T) equals to unity (1) along the selected chemical potential range at different temperatures. The summed-up properties and the overall tendency triggers the possibility of these materials to register their extending applications in spintronics, thermoelectrics, nanoengineering, and radioisotope generator perspectives.
由于从基础科学和应用导向两个方面来看，半金属钙钛矿意外加速发现的情况持续增加。在此，在本研究工作中，我们首次在统一密度泛函理论范围内，对实验合成的一种钙钛矿结构BaErNbO以及与之相关的BaTmNbO进行了详细分析。首先，通过对布里奇曼-莫纳汉状态方程的展开，根据两种分子钙钛矿结构的总基态和内聚能，严格确定了它们的结构稳定性。此外，容差因子（τ）可监测立方结构稳定性，且不存在任何几何应变。更有可能的是，密度泛函微扰理论（DFPT）已被校准，以了解这些层状结构的动力学情况。同样，从二阶弹性和力学参数的理解出发，阐述了它们合适的韧性特征。通过利用广义梯度近似（GGA）、针对特定角动量的强关联电子选择的在位哈伯德方案（GGA + U）以及修正的贝克-约翰逊（mBJ）势，系统地调整了它们固有电子结构的量子力学精细化。此外，围绕费米能级（E）的非对称态密度（DOS）的二维表示以及与其相应自旋极化能带结构相关的解释，标志着众所周知的半金属性质。随后，在不同温度下，沿选定的化学势范围，输运性质尤其是品质因数（T）的值等于1。总结出的性质和总体趋势引发了这些材料在自旋电子学、热电学、纳米工程和放射性同位素发生器等方面扩展应用的可能性。
