Nonreciprocal transport in a room-temperature chiral magnet

TL;DR

This study investigates nonreciprocal electron transport in a room-temperature chiral magnet, identifying distinct mechanisms such as spin-fluctuation-induced scattering and band asymmetry through experimental and theoretical analysis.

Contribution

It provides the first clear separation and identification of different nonreciprocal transport mechanisms in a single room-temperature chiral magnet.

Findings

Nonreciprocal resistivity varies with field and temperature.

Distinct contributions from spin-fluctuation scattering and band asymmetry are identified.

Mechanisms are confirmed through theoretical calculations.

Abstract

Chiral magnets under broken time-reversal symmetry can give rise to rectification of moving electrons, called nonreciprocal transport. Several mechanisms, such as the spin-fluctuation-induced chiral scattering and asymmetry in the electronic band dispersion with and without the relativistic spin-orbit interaction, have been proposed, but clear identification as well as theoretical description of these different contributions are desired for full understanding of nonreciprocal transport phenomena. Here, we investigate a chiral magnet Co8Zn9Mn3 and find the nonreciprocal transport phenomena consisting of different contributions with distinct field- and temperature-dependence across the magnetic phase diagram over a wide temperature range including above room-temperature. We successfully separate the nonreciprocal resistivity into different components and identify their mechanisms as spin-fluctuation-induced chiral scattering and band asymmetry in a single material with the help of theoretical calculations.