Nonlocal transport in Weyl semimetals in the hydrodynamic regime

TL;DR

This paper investigates the nonlocal electrical response in Weyl semimetals within the hydrodynamic regime, revealing topological effects such as asymmetrical electron flow, negative resistance, and anomalous Hall currents influenced by the material's chiral properties.

Contribution

It introduces a hydrodynamic framework to analyze topological and nonlocal effects in Weyl semimetals, highlighting the impact of Chern-Simons terms on electron flow and resistance.

Findings

Chern-Simons terms cause spatial asymmetry in electron flow.

Topological effects can induce negative nonlocal resistance.

Anomalous Hall current depends on electric field distribution and chiral shift orientation.

Abstract

The nonlocal response of chiral electron fluid in a semi-infinite Weyl semimetal slab with the electric current source and drain attached to its surface is studied by using the consistent hydrodynamic framework. It is found that the Chern-Simons terms lead to a spatial asymmetry of the electron flow and the electric field. Most remarkably, the corresponding topological terms could result in a negative nonlocal resistance. In addition, they give rise to the anomalous Hall current, which is sensitive to the spatial distribution of the electric field in the plane of the contacts and depends on the orientation of the chiral shift.