论文标题
手性带结构的涡度效应
Vortical effects in chiral band structures
论文作者
论文摘要
手性涡旋效应是手性异常引起的转运现象,其特征在于均匀旋转的手性液中的轴向电流。对于高能物理学中的Weyl Fermions来说,它是被理解的,但是它在凝聚的物质带结构(包括Weyl Semimetals)中的实现一直存在争议。在这项工作中,我们开发了一般条带结构中电子的Kubo响应理论,但相对于背景晶格的空间和时间依赖性旋转或涡度。我们在静态极限中恢复了手性涡旋效应。在运输或统一的极限中,我们发现了一种新的效果,可以将陀螺仪涡流效应配音。后者由占用带的浆果曲率控制,而前者则包含电子表面上电子磁矩的额外贡献。这两个涡旋效应可以理解为手性带结构中众所周知的手性和旋转磁效应的类似物。我们解决了该领域的最新争议,并通过描述利用欧姆或Seebeck运输以驱动涡旋效应的设备几何形状来结束。
The chiral vortical effect is a chiral anomaly induced transport phenomenon characterized by an axial current in a uniformly rotating chiral fluid. It is well-understood for Weyl fermions in high energy physics, but its realization in condensed matter band structures, including those of Weyl semimetals, has been controversial. In this work, we develop the Kubo response theory for electrons in a general band structure subject to space- and time-dependent rotation or vorticity relative to the background lattice. We recover the chiral vortical effect in the static limit; in the transport or uniform limit, we discover a new effect that we dub the gyrotropic vortical effect. The latter is governed by Berry curvature of the occupied bands while the former contains an additional contribution from the magnetic moment of electrons on the Fermi surface. The two vortical effects can be understood as analogs of the well-known chiral and gyrotropic magnetic effects in chiral band structures. We address recent controversies in the field and conclude by describing device geometries that exploit Ohmic or Seebeck transport to drive the vortical effects.