title: Spin current and magnetoelectric effect in noncollinear magnets.
abstract: A new mechanism of the magnetoelectric effect based on the spin supercurrent is theoretically presented in terms of a microscopic electronic model for noncollinear magnets. The electric polarization P(ij) produced between the two magnetic moments S(i) and S(j) is given by P proportional e(ij) X (S(i) X S(j)) with e(ij) being the unit vector connecting the sites i and j. Applications to the spiral spin structure and the gauge theoretical interpretation are discussed.
authors.affiliation: Department of Applied Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan. katsura@appi.t.u-tokyo.ac.jp
authors.forename: Hosho
authors.initials: H
authors.lastname: Katsura
authors.forename: Naoto
authors.initials: N
authors.lastname: Nagaosa
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Balatsky