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arXiv · 1707.02776

Spontaneous and Superfluid Chiral Edge States in Exciton-Polariton Condensates

H. Sigurdsson·G. Li·T. C. H. Liew
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Abstract

We present a scheme of interaction-induced topological bandstructures based on the spin anisotropy of exciton-polaritons in semiconductor microcavities. We predict theoretically that this scheme allows the engineering of topological gaps, without requiring a magnetic field or strong spin-orbit interaction (transverse electric-transverse magnetic splitting). Under non-resonant pumping, we find that an initially topologically trivial system undergoes a topological transition upon the spontaneous breaking of phase symmetry associated with polariton condensation. Under resonant coherent pumping, we find that it is also possible to engineer a topological dispersion that is linear in wavevector -- a property associated with polariton superfluidity.

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H. Sigurdsson, G. Li, T. C. H. Liew. 2017-07-10. Spontaneous and Superfluid Chiral Edge States in Exciton-Polariton Condensates. https://doi.org/10.1103/physrevb.96.115453

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