Gigantic magnetochiral anisotropy in the topological semimetal ZrTe5

TL;DR

This study reports the discovery of the largest magnetochiral anisotropy ever observed in ZrTe5, a topological semimetal near a quantum phase transition, driven by unique electronic properties and symmetry breaking.

Contribution

It reveals that ZrTe5 exhibits gigantic magnetochiral anisotropy due to low carrier density and Fermi surface topology near a topological phase transition.

Findings

Gigantic magnetochiral anisotropy observed in ZrTe5

Largest ever magnetochiral anisotropy recorded

Low carrier density and Fermi surface shape are key factors

Abstract

Topological materials with broken inversion symmetry can give rise to nonreciprocal responses, such as the current rectification controlled by magnetic fields via magnetochiral anisotropy. Bulk nonreciprocal responses usually stem from relativistic corrections and are always very small. Here we report our discovery that ZrTe5 crystals in proximity to a topological quantum phase transition present gigantic magnetochiral anisotropy, which is the largest ever observed to date. We argue that a very low carrier density, inhomogeneities, and a torus-shaped Fermi surface induced by breaking of inversion symmetry in a Dirac material are central to explain this extraordinary property.