Control of multiferroic order by magnetic field in frustrated helimagnet MnI. Theory
arXiv:1807.01693 · doi:10.1016/j.jmmm.2018.11.099
Abstract
We provide a theoretical description of frustrated multiferroic with a spiral magnetic ordering in magnetic field . We demonstrate that subtle interplay of exchange coupling, dipolar forces, hexagonal anisotropy, and the Zeeman energy account for the main experimental findings observed recently in this material (Kurumaji, et al., Phys.\ Rev.\ Lett.\ {\bf 106}, 167206 (2011)). We describe qualitatively the non-trivial evolution of electric polarization upon rotation, changing direction upon increasing, and disappearance of ferroelectricity at , where is smaller than the saturation field.
5 pages, 5 figures