Topological Interface States in a Polariton SSH Lattice: Linear and Nonlinear Regimes

Exploring topological physics in photonic systems is a promising avenue for developing novel generation of optical devices that are robust against external perturbations and fabrication defects [1]. It is however still challenging to implement topological lattices in media exhibiting strong optical nonlinearities, which is a necessary requirement for exploring the confluence of nonlinear optics and topological robustness. Hence, cavity polaritons formed from the strong coupling between quantum well excitons and cavity photons are particularly appealing: their photonic part allows for engineering topological properties in lattices of coupled micropillars [2], while their excitonic part gives rise to strong Kerr-like nonlinearities and to lasing [3].