Electric and thermoelectric response for Weyl and multi-Weyl semimetals in planar Hall configurations including the effects of strain

TL;DR

This paper explores how electric and thermoelectric responses in Weyl and multi-Weyl semimetals are affected by strain-induced pseudomagnetic fields and magnetic fields in planar Hall configurations, revealing dependence on topological charge and orientation.

Contribution

It introduces a comprehensive analysis of the combined effects of physical and pseudomagnetic fields on response tensors in Weyl semimetals, including strain effects and topological charge dependence.

Findings

Response tensors are sensitive to the orientation of magnetic fields and electric/thermal gradients.

Conductivity profiles depend strongly on the topological charge of the Weyl nodes.

Strain-induced pseudomagnetic fields significantly influence the electronic response characteristics.

Abstract

We investigate the response tensors in planar Hall (or planar thermal Hall) configurations such that a three-dimensional Weyl or multi-Weyl semimetal is subjected to the influence of an electric field $\mathbf E $ (or temperature gradient $\nabla_{\mathbf r } T$) and an effective magnetic field $\mathbf B^{\rm tot}$, which are oriented at a generic angle with respect to each other. The effective magnetic field consists of two parts: (a) an actual/physical magnetic field $\mathbf B $, and (b) an emergent magnetic field $\mathbf B_5 $ which quantifies the elastic deformations of the sample. $\mathbf B_5 $ is an axial pseudomagnetic field because it couples to conjugate nodal points with opposite chiralities with opposite signs. We study the interplay of the orientations of these two components of $\mathbf B^{\rm tot}$ with respect to the direction of the electric field (or temperature gradient) and elucidate how it affects the characteristics involving the chirality of the node. Additionally, we show that the magnitude and sharpness of the conductivity tensor profiles strongly depend on the value of the topological charge at the node in question.