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Electronic Mechanism for the Coexistence of Ferroelectricity and Ferromagnetism

C. D. Batista·J. E. Gubernatis·Wei-Guo Yin
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Abstract

We study the strong coupling limit of a two-band Hubbard Hamiltonian that also includes an inter-orbital on-site repulsive interaction $U_{ab}$. When the two bands have opposite parity and are quarter filled, we prove that the ground state is simultaneously ferromagnetic and ferroelectric for infinite intra-orbital Coulomb interactions $U_{aa}$ and $U_{bb}$. We also show that this coexistence leads to a singular magnetoelectric effect.

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C. D. Batista, J. E. Gubernatis, Wei-Guo Yin. 2005-10-19. Electronic Mechanism for the Coexistence of Ferroelectricity and Ferromagnetism. https://arxiv.org/abs/cond-mat/0508113

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