2019/08/13 by Hiroaki Ishizuka, Naoto Nagaosa · 1 citation
Physics and Astronomy · #cond-mat.str-el #cond-mat.mes-hall
paper · pdf · doi:10.1038/s41467-020-16751-2
published as Nat. Commun. 11, 2986 (2020) · 6 pages, 2 figures
arxiv created 2019/08/13 · arxiv updated 2021/08/31
The non-collinear spin configurations cause many nontrivial phenomena related to the Berry phase. They are described by the vector spin chirality χij =\bf Si×\bf Sj or scalar spin chirality χijk=(\bf Si × \bf Sj) ⋅ \bf Sk, which are related to the spin current and effective magnetic field, respectively. The scalar spin chirality leads to the topological Hall effect in metals, while the vector spin chirality to the ferroelectricity of spin origin, i.e., multiferroics in insulators. However, the role of the vector spin chirality in conducting systems has not yet elucidated. Here we show theoretically that the spin fluctuation with vector spin chirality in chiral magnets scatters electrons asymmetrically, resulting in a nonreciprocal transport phenomena, i.e., electrical magnetochiral effect (eMChE). This asymmetric scattering appears in the leading-order scattering term, implying a large nonreciprocity in the charge and spin currents. We find that the temperature and magnetic field dependence of the eMChE reproduces that observed in MnSi. Our results reveal the microscopic mechanism of eMChE and its potential in producing a large nonreciprocal response.