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arXiv · 1211.6386

A Non-Commutative Formula for the Isotropic Magneto-Electric Response

Bryan Leung·Emil Prodan
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Abstract

A non-commutative formula for the isotropic magneto-electric response of disordered insulators under magnetic fields is derived using the methods of non-commutative geometry. Our result follows from an explicit evaluation of the Ito derivative with respect to the magnetic field of the non-commutative formula for the electric polarization reported in Ref. 1. The quantization, topological invariance and connection to a second Chern number of the magneto-electric response are discussed in the context of 3-dimensional, disordered, time-reversal or inversion symmetric topological insulators.

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Bryan Leung, Emil Prodan. 2012-12-19. A Non-Commutative Formula for the Isotropic Magneto-Electric Response. https://doi.org/10.1088/1751-8113%2F46%2F8%2F085205

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