Berry-curvature-induced linear magnetotransport in magnetic Weyl semimetals

TL;DR

This paper identifies Berry curvature as a key mechanism behind linear magnetotransport in magnetic Weyl semimetals, explaining recent experimental observations and highlighting its tunability and detectability through Hall effect and magnetoresistance.

Contribution

It reveals Berry curvature as a dominant cause of linear magnetotransport in magnetic Weyl semimetals, expanding understanding of magnetotransport phenomena.

Findings

Berry curvature induces significant linear magnetotransport conductivities.

LMT can reach orders of 10^4 and 10^2 Ω^{-1}m^{-1} per tesla in specific materials.

Intrinsic magnetoresistance exceeding 100% per tesla is detectable regardless of sample quality.

Abstract

Magnetotransport such as the giant magnetoresistance and Hall effect lies at the heart of fundamental physics and technologies. Recently, some experiments have clearly demonstrated linear magnetotransport (LMT) proportional to magnetic field but the underlying physical mechanism is still unclear. In this work, we show that Berry curvature effect is a new mechanism dominating the LMT. The Berry-curvature-induced LMT widely exists in 66 out of 122 magnetic point groups. For typical magnetic Weyl semimetals Co$_3$Sn$_2$S$_2$ and ferromagnetic MnBi$_2$Te$_4$, Berry curvature induces LMT conductivities reaching orders of $10^4$ and $10^2$ ${\rm \Omega^{-1}m^{-1}}$ per tesla, respectively, which are tunable through magnetization canting induced by moderate magnetic fields. We further reveal that Berry-curvature-induced LMT can be detected by Hall effect and especially intrinsic magnetoresistance exceeding $100\%$ per tesla insensitive to the sample quality. Our results agree with recent experiments and uncover the important role of Berry curvature in LMT.