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arXiv · 2202.04471

Domain-wall topology induced by spontaneous symmetry breaking in polariton graphene

D. D. Solnyshkov·C. Leblanc·I. Septembre·G. Malpuech
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Abstract

We present a numerical study of exciton-polariton (polariton) condensation in a staggered polariton graphene showing a gapped s-band at the $K$ and $K'$ valleys. The condensation occurs at $K$ or $K'$, at the kinetically-favorable negative mass extrema of the valence band. Considering attractive polariton-polariton interaction allows to generate a spatially extended condensate. Spontaneous symmetry breaking occurring during the condensate build-up leads to the formation of valley-polarized domains following the Kibble-Zurek scenario. The selection of a single valley breaks time-reversal symmetry and the walls separating domains exhibit a topologically-protected chiral current. This current therefore emerges as a result of the interplay between the non-trivial valley topology and the condensation-induced symmetry breaking.

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D. D. Solnyshkov, C. Leblanc, I. Septembre, G. Malpuech. 2022-02-09. Domain-wall topology induced by spontaneous symmetry breaking in polariton graphene. https://doi.org/10.1103/physrevlett.129.066802

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