Beyond Dicke superradiance: matter-wave emission from polaritonic quantum matter.

State-selective optical lattices have the capability of hosting ‘matter-wave polaritons’ (quasiparticles analogous to exciton-polaritons) by coupling lighter and heavier states of ultracold atoms [1]. In this talk, we discuss how a recent dynamical study of such a system [2] can be understood, in the highly coherent regime, as a collective de-excitation of an array of distant quantum emitters featuring diverse phenomena such as super- and subradiance, (quasi-)bound states in the continuum and directional emission induced by retardation. This contrasts with the strongly correlated case, which can lead to the buildup of excitonic coherence through collective spontaneous emission.

[1] J. Kwon, Y. Kim, A. Lanuza, D. Schneble, “Formation of matter-wave polaritons in an optical lattice”, Nat. Phys. 18, 657-661 (2022).

[2] Y. Kim, A. Lanuza, D. Schneble, talk given at this conference.