The spin ordering and spin-charge coupling in LuFe2O4 were investigated on the basis of density functional calculations and Monte Carlo simulations. The 2:1 ferrimagnetism arises from the strong antiferromagnetic intra-sheet Fe3+-Fe3+ and Fe3+ -Fe2+ as well as some substantial antiferromagnetic Fe2+-Fe3+ inter-sheet spin exchange interactions. The giant magnetocapacitance at room temperature and the enhanced electric polarization at 240 K of LuFe2O4 are explained by the strong spin-charge coupling.
@article{arxiv.0812.3897,
title = {Origin of the Ising Ferrimagnetism and Spin-Charge Coupling in LuFe2O4},
author = {H. J. Xiang and E. J. Kan and Su-Huai Wei and M. -H. Whangbo and Jinlong Yang},
journal= {arXiv preprint arXiv:0812.3897},
year = {2009}
}