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arXiv · 1809.02819

Photonic emulation of two-dimensional materials with antiferromagnetic order

Ran Gladstein Gladstone·Minwoo Jung·Yuchen Han·Gennady Shvets
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Abstract

We introduce an electromagnetic metamaterial - a spin-valley photonic topological insulator (SV-PTI) - that emulates a wide class of theoretically predicted gapped two-dimensional materials with antiferromagnetic order coupled to the valley degree of freedom. First-principles electromagnetic simulations and an analytic model reveal that a single parameter controls the propagation properties of the chiral states at the domain wall between two SV-PTIs: their group velocity, polarization, and the existence/absence of topological protection. The latter is determined by the geometry of the line of the least frequency separation between the bandgap-forming propagation bands. Topologically-protected compression of electromagnetic energy via group velocity control is enabled by SV-PTIs.

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Ran Gladstein Gladstone, Minwoo Jung, Yuchen Han, Gennady Shvets. 2019-04-12. Photonic emulation of two-dimensional materials with antiferromagnetic order. https://doi.org/10.1103/physrevb.100.245417

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