We report novel magnetoelectric properties of a quantum-spin helimagnet Ba2CuGe2O7 with a noncentrosymmetric (but nonpolar) crystal structure. It was found that the spin helicity of the cycloidal spin order is always fixed to the lattice, therefore the magnetic propagation vector k determines the sign of electric polarization in Ba2CuGe2O7. Consequently, not only the magnetic-field drive of the ferroelectric domain but also the electric-field switching of magnetic k vector can be achieved.
ASJC Scopus subject areas
- Physics and Astronomy(all)