论文标题
自旋轨道耦合效应在稀土金属四孔中的作用：第一个主要研究
Role of spin-orbit coupling effects in rare-earth metallic tetra-borides : a first principle study
论文作者
论文摘要
我们使用了量子意式浓缩咖啡（QE）实现的第一原理电子结构方法（DFT），研究了稀有四位烷的电子结构，$ \ textrm {rb} _ {4} $。在本文中，我们研究了这些系统中对这些系统对这些系统在非磁基态的电子结构中存在的强旋转轨道耦合（SOC）效应的强烈旋转轨道效果（SOC）。计算是在GGA和GGA+下完成的，因此使用Ultrasoft伪电势和完全相对论的Ultrasoft Pseudoptentials（对于SOC案例）进行近似。使用了QE中实现的线性化平面波（LAPW）方法中的Perdew-Burke-Ernzerhof广义梯度近似（PBE-GGA）交换相关功能。状态的预计密度由3个不同的光谱峰组成，远低于费米能，并与费米能量周围状态的连续密度分开。离散的峰值是由于稀有地球$ s $ s $ orbital，稀有地球$ p $ + b $ p $和b $ p $ - 轨道的，而连续体是由于杂交b $ p $，稀有$ d $ d $ orbitals引起的。包含SOC后，由于稀有地球$ p $ - 轨道而引起的峰分为两个峰，对应于$ j = 0.5 $，$ j = 1.5 $构造。如果$ \ textrm {lab} _ {4} $在存在SOC的情况下，Spin-Split $ 4F $ Orbitals在费米水平上有助于状态的密度，而费米级别的状态密度在很大程度上仍未受到所有其他材料的影响。
We have investigated the electronic structure of rare-earth tetraborides, $\textrm{RB}_{4}$, using first-principle electronic structure methods (DFT) implemented in Quantum Espresso (QE). In this article we have studied heather-to neglected strong spin-orbit coupling (SOC) effects present in these systems on the electronic structure of these system in the non-magnetic ground state. The calculations were done under GGA and GGA+SO approximations using ultrasoft pseudopotentials and fully relativistic ultrasoft pseudopotentials (for SOC case). Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA) exchange-correlation functionals within the linearized plane-wave (LAPW) method as implemented in QE were used. The projected density of states consists of 3 distinct spectral peaks well below the Fermi energy and separated from the continuum density of states around the Fermi energy. The discrete peaks arises due to rare-earth $s$-orbital, rare-earth $p$ + B $p$ and B $p$-orbitals while the continuum arises due to hybridized B $p$, rare-earth $d$ orbitals. Upon inclusion of SOC the peak arising due to rare-earth $p$-orbitals gets split into two peaks corresponding to $j=0.5$ and $j=1.5$ configurations. In case of $\textrm{LaB}_{4}$, in the presence of SOC, spin-split $4f$ orbitals contributes to density of states at the Fermi level while the density of states at the Fermi level largely remains unaffected for all other materials under consideration.
