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arXiv · 0905.3033

First-principles theory of magnetically induced ferroelectricity in TbMnO3

Andrei Malashevich·David Vanderbilt
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Abstract

We study the polarization induced via spin-orbit interaction by a magnetic cycloidal order in orthorhombic TbMnO3 using first-principle methods. The case of magnetic spiral lying in the b-c plane is analyzed, in which the pure electronic contribution to the polarization is shown to be small. We focus our attention on the lattice-mediated contribution, and study it's dependence on the Coulomb interaction parameter U in the LDA+U method and on the wave-vector of the spin spiral. The role of the spin-orbit interaction on different sites is also analyzed.

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Andrei Malashevich, David Vanderbilt. 2009-05-19. First-principles theory of magnetically induced ferroelectricity in TbMnO3. https://doi.org/10.1140/epjb/e2009-00208-2

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