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arXiv · 1512.00534

Dynamical Axion Field in a Magnetic Topological Insulator Superlattice

Jing Wang·Biao Lian·Shou-Cheng Zhang
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Abstract

We propose that the dynamical axion field can be realized in a magnetic topological insulator superlattice or a topological paramagnetic insulator. The magnetic fluctuations of these systems produce a pseudoscalar field which has an axionic coupling to the electromagnetic field, and thus it gives a condensed-matter realization of the axion electrodynamics. Compared to the previously proposed dynamical axion materials where a long range antiferromagnetic order is required, the systems proposed here have the advantage that only a uniform magnetization or a paramagnetic state is needed for the dynamic axion. We further propose several experiments to detect such a dynamical axion field.

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Jing Wang, Biao Lian, Shou-Cheng Zhang. 2015-12-02. Dynamical Axion Field in a Magnetic Topological Insulator Superlattice. https://doi.org/10.1103/physrevb.93.045115

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