Dielectric susceptibility of magnetoelectric thin films with vortex-antivortex dipole pairs

P. I. Karpov; S. I. Mukhin

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arXiv · 1506.07856

Dielectric susceptibility of magnetoelectric thin films with vortex-antivortex dipole pairs

P. I. Karpov·S. I. Mukhin

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Abstract

We consider model of quasi-2D magnetoelectric material as XY model for spin system on a lattice with local multiferroic-like interaction of spin and electric polarization vectors. We calculate the contribution of magnetic (spin) vortex-antivortex pairs (which form electric dipoles) to the dielectric susceptibility of the system. We show that in approximation of non-interacting pairs at $T \rightarrow T_{BKT}$ (Berezinskii-Kosterlitz-Thouless temperature) dielectric susceptibility diverges.

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P. I. Karpov, S. I. Mukhin. 2015-06-25. Dielectric susceptibility of magnetoelectric thin films with vortex-antivortex dipole pairs. https://arxiv.org/abs/1506.07856

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