2025/03/30 by Yamaguchi, Daiki, Kitaori, Aki, Nagaosa, Naoto +1 · 4 citations
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci)
paper · doi:10.48550/arxiv.2503.23261
A multiferroic state with both electric polarization (P) and magnetization (M) shows the inherently strong P-M coupling, when P is induced by cycloidal (Néel-wall like) spin modulation. The sign of P is determined by clockwise or counterclockwise rotation of spin, termed the spin helicity. Such a multiferroic state is not limited to magnetic insulators but can be broadly observed in conductors. Here, we report the current-induced magnetoelectric control of the multiferroics in a helimagnetic metal YMn6Sn6 and its detection through nonreciprocal resistivity (NRR). The underlying concept is the coupling of the current with the toroidal moment T ∼ P × M ∼ (q × χv) × M as well as with the magneto-chirality χv × M, where q and χv being the unit modulation wave vector and the vector spin chirality, respectively. We furthermore observe an enhancement of NRR by the spin-cluster scattering via χv and its fluctuation. These findings may pave a way to exploration of multiferroic conductors and application of the spin-helicity degree of freedom as a state-variable.