Exciton-Polariton Gas as a Nonequilibrium Coolant

Sebastian Klembt (1) , Emilien Durupt (1) , Sanjoy Datta (2) , Thorsten Klein (3) , Augustin Baas (1) , Yoan Léger (4) , Carsten Kruse (3) , Detlef Hommel (3) , Anna Minguzzi (2) , Maxime Richard (1)

1 NEEL - NPSC - Nanophysique et Semiconducteurs
2 LPM2C - Laboratoire de physique et modélisation des milieux condensés
3 Universität Bremen
4 FOTON - Fonctions Optiques pour les Technologies de l'informatiON

Using angle-resolved Raman spectroscopy, we show that a resonantly excited ground-state excitonpolariton fluid behaves like a nonequilibrium coolant for its host solid-state semiconductor microcavity. With this optical technique, we obtain a detailed measurement of the thermal fluxes generated by the pumped polaritons. We thus find a maximum cooling power for a cryostat temperature of 50 K and below where optical cooling is usually suppressed, and we identify the participation of an ultrafast cooling mechanism. We also show that the nonequilibrium character of polaritons constitutes an unexpected resource: each scattering event can remove more heat from the solid than would be normally allowed using a thermal fluid with normal internal equilibration.

Domaines: Gaz Quantiques [cond-mat.quant-gas]; Physique Quantique [quant-ph]

Sebastian Klembt, Emilien Durupt, Sanjoy Datta, Thorsten Klein, Augustin Baas, et al.. Exciton-Polariton Gas as a Nonequilibrium Coolant. Physical Review Letters, 2015, 114 (18), pp.186403. ⟨10.1103/PhysRevLett.114.186403⟩. ⟨hal-01152647⟩