Multiferroics seen from theoretic derivation of a tight binding model

Tian De Cao

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arXiv · 0908.1232

Multiferroics seen from theoretic derivation of a tight binding model

Tian De Cao

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Abstract

One presented some lattice models, while the theoretic derivation has not been found, and the importance of correlation effects has to be emphasized. On the basis of the non-relativistic Hamiltonian from the Dirac equation, we derive in detail a tight binding model. We find that both ferromagnetism and ferroelectricity are from the correlation effect between electrons, and magnetic and electric orders are strongly coupled due to the spin-orbit interaction.

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Tian De Cao. 2009-08-24. Multiferroics seen from theoretic derivation of a tight binding model. https://arxiv.org/abs/0908.1232

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