论文标题
Weyl半法中的量化电化学转运
Quantized electrochemical transport in Weyl semimetals
论文作者
论文摘要
我们表明，在外部电场和化学电位的梯度的效果下，可以在无倒反转和镜像对称性的Weyl半学中诱导拓扑电流。我们得出非线性电导率张量的分析表达式，并表明当费米水平接近Weyl节点时，它几乎对小倾斜进行了量化。当van霍夫点比最大的费米水平大得多时，通过两种线性分散的韦尔福尔米（Weyl fermions）用相反的手性来描述频带结构。在这种情况下，用基本常数和散射时间对电化学响应进行了充分量化，并且可以用来直接测量Weyl点的拓扑电荷。我们表明，电化学手性电流可以源自类似于轴支电动力学的电磁作用，在该动作中，轴突电动力学的位置依赖性手性费米水平起着轴支球场的作用。这将我们的结果视为手性异常的直接结果。
We show that under the effect of an external electric field and a gradient of chemical potential, a topological electric current can be induced in Weyl semimetals without inversion and mirror symmetries. We derive analytic expressions for the nonlinear conductivity tensor and show that it is nearly quantized for small tilting when the Fermi levels are close to the Weyl nodes. When the van Hove point is much larger than the largest Fermi level, the band structure is described by two linearly dispersing Weyl fermions with opposite chirality. In this case, the electrochemical response is fully quantized in terms of fundamental constants and the scattering time, and it can be used to measure directly the topological charge of Weyl points. We show that the electrochemical chiral current may be derived from an electromagnetic action similar to axion electrodynamics, where the position-dependent chiral Fermi level plays the role of the axion field. This posits our results as a direct consequence of the chiral anomaly.
