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arXiv · 2304.14998

Polariton vortex Chern insulator

Stella L. Harrison·Anton Nalitov·Pavlos G. Lagoudakis·Helgi Sigurðsson
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Abstract

We propose a vortex Chern insulator, motivated by recent experimental demonstrations on programmable arrangements of cavity polariton vortices by [Alyatkin et al., ArXiv:2207.01850 (2022)] and [Wang et al., National Sci. Rev. 10, Nwac096 (2022)]. In the absence of any external fields, time-reversal symmetry is spontaneously broken through polariton condensation into structured arrangements of localized co-rotating vortices. We characterize the response of the rotating condensate lattice by calculating the spectrum of Bogoliubov elementary excitations and observe the crossing of edge-states, of opposite vorticity, connecting bands with opposite Chern numbers. The emergent topologically nontrivial energy gap stems from inherent vortex anisotropic polariton-polariton interactions and does not require any spin-orbit coupling, external magnetic fields, or elliptically polarized pump fields.

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Stella L. Harrison, Anton Nalitov, Pavlos G. Lagoudakis, Helgi Sigurðsson. 2023-05-01. Polariton vortex Chern insulator. https://doi.org/10.1364/ome.494448

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