Nonreciprocal transport in a room-temperature chiral magnet.

Nakamura, Daisuke; Lee, Mu-Kun; Karube, Kosuke; Mochizuki, Masahito; Nagaosa, Naoto; Tokura, Yoshinori; Taguchi, Yasujiro · Sci Adv · 2025

basic_science · Level V

Where this comes from

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 and theoretical description of these different contributions are desired for full understanding of nonreciprocal transport phenomena. Here, we investigate a chiral magnet Co<sub>8</sub>Zn<sub>9</sub>Mn<sub>3</sub> 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.