论文标题
weyl半金属laal $ x $（$ x $ = si，ge）中的大型旋转大厅角的起源和大型增强
Origin and Large Enhancement of Large Spin Hall Angle in Weyl Semimetals LaAl$X$ ($X$=Si, Ge)
论文作者
论文摘要
我们在最近发现的Weyl Semimetals家族中研究了强旋霍尔效应（SHA）的起源，laal $ x $（$ x $ = si，ge，ge）通过具有最大局部局部Wannier功能的第一原理方法。我们表明，在Laal $ x $中，强大的内在性来自$ e_f $的节点线和点附近的多个轻微的抗骨骼，这是由于它们的高镜子对称性和大型旋转轨道相互作用。进一步发现，电气和热手段都可以增强旋转厅电导率（$σ_{sh} $）。但是，前者还增加了电导率（$σ_{C} $），而后者则减少了电导率。结果，$σ_{sh} $和$σ_{c} $的独立调整可以增强旋转霍尔角（与$ \ frac {σ_{sh}} {σ_{s sh}} {σ_{c}} $），这是电荷当前的Spin-conterconverseconconverseconconversion spin-Oribit spin-orbit device的功绩。通过频带分辨和$ k $分辨的自旋浆果曲率揭示了这种独立变化的自旋大厅和通过热手段电导率的基本物理。我们的发现为搜索高SHA材料的新方法提供了一种新的方式，以用于室温旋转轨道人。
We study the origin of the strong spin Hall effect (SHE) in a recently discovered family of Weyl semimetals, LaAl$X$ ($X$=Si, Ge) via a first-principles approach with maximally localized Wannier functions. We show that the strong intrinsic SHE in LaAl$X$ originates from the multiple slight anticrossings of nodal lines and points near $E_F$ due to their high mirror symmetry and large spin-orbit interaction. It is further found that both electrical and thermal means can enhance the spin Hall conductivity ($σ_{SH}$). However, the former also increases the electrical conductivity ($σ_{c}$), while the latter decreases it. As a result, the independent tuning of $σ_{SH}$ and $σ_{c}$ by thermal means can enhance the spin Hall angle (proportional to $\frac{σ_{SH}}{σ_{c}}$), a figure of merit of charge-to-spin current interconversion of spin-orbit torque devices. The underlying physics of such independent changes of the spin Hall and electrical conductivity by thermal means is revealed through the band-resolved and $k$-resolved spin Berry curvature. Our finding offers a new way in the search of high SHA materials for room-temperature spin-orbitronics applications.
