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arXiv · 2010.01372

Vector Potential and Surface Magnetic Field in Magnetoelectric Antiferromagnetic Materials

Zeyu Jiang·Damien West·Shengbai Zhang
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Abstract

A general formula for the average vector potential of bulk periodic systems is proposed and shown to set the boundary conditions at magnetic interfaces. For antiferromagnetic materials, the study reveals a unique relation between the macroscopic potential and the orientation-dependent magnetic quadrupole, as a result of the different crystalline and magnetic symmetries. In particular, at surfaces and interfaces of a truncated bulk without inversion and time-reversal symmetries, the average vector potential exhibits a discontinuity, which results in an interfacial magnetic field. In general, however, due to the surface and interface electronic and atomic relaxations, additional magnetization may result. For the experimentally-observed magnetoelectric antiferromagnets, in particular, our symmetry analysis suggest that the relaxation effects could well be a system response to the presence of such a potential discontinuity.

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Zeyu Jiang, Damien West, Shengbai Zhang. 2020-11-11. Vector Potential and Surface Magnetic Field in Magnetoelectric Antiferromagnetic Materials. https://doi.org/10.1103/physrevb.102.174411

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