The magnetoelectric effects in weak ferromagnetic YMn2O5 modulated structure: a Landau theory approach
Department of Physics and Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Evin, Tehran, 19839, Iran
2 Department of Physics, Azarbaijan University of Tarbiat Moallem, 35th km Tabriz-Maragheh Road, 53714-161, Tabriz, Iran
Corresponding author: a Phirouznia@azaruniv.edu
Published online: 12 May 2010
According to the group theory approach, linear magnetoelectric effect (ME) can not be obtained for the spatial group of YMn2O5, which was known to be mmm. Regard to the magnetic structure of these type of materials, we propose a magnetic group structure for the YMn2O5 by considering spin orientation of the Mn3+ and Mn4+ ions. According to the landau theory of phase transition it can be shown, how symmetrical rules result in relationship between quantities such as magnetic order, polarization, and etc. This relation shows a weak ferromagnetic state, associated with spontaneous polarization, arisen by Dzyaloshinskii-Moriya type interaction and a field induced change in magnetoelectrical susceptibility.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2010