Bond electronic polarization induced by spin

摘要: We study theoretically the electric polarization induced by noncollinear spin configurations in limit of strong Hund coupling. employ a model two magnetic ions sandwiching an oxygen ion. It is shown that there appears longitudinal ${P}_{x}$ along bond, which roughly proportional to ${({m}_{r}^{x})}^{2}\ensuremath{-}{({m}_{l}^{x})}^{2}$ where ${m}_{r(l)}^{x}$ $x$ component orientation vector at right (left) A numerical Hamiltonian yields both and transverse dipole moments. The have nonuniform as well uniform component, with latter being consistent previous theory. oscillating period half order, but local magnitude typically much larger than may be detected x-ray/neutron scattering experiments.