Unstable and stable regimes of polariton condensation

F. Baboux (1, 2) , D. de Bernardis (3) , V. Goblot (2) , V. Gladilin (3) , C. Gomez (2) , E. Galopin (4, 2) , L. Le Gratiet (4, 2) , A. Lemaître (2) , I. Sagnes (4, 2) , I. Carusotto (5) , M. Wouters (3) , A. Amo (6, 2) , J. Bloch (2)

1 INSP - Institut des Nanosciences de Paris
2 C2N - Centre de Nanosciences et de Nanotechnologies
3 TQC - Theory of Quantum systems and Complex systems
4 LPN - Laboratoire de photonique et de nanostructures
5 INO-CNR BEC Center and Dipartimento di Fisica
6 PhLAM - Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523

Modulational instabilities play a key role in a wide range of nonlinear optical phenomena, leading, e.g., to the formation of spatial and temporal solitons, rogue waves, and chaotic dynamics. Here, we experimentally demonstrate the existence of a modulational instability in condensates of cavity polaritons, quasi-particles arising from the strong coupling of cavity photons with quantum well excitons. For this purpose, we investigate the spatiotemporal coherence properties of polariton condensates in GaAs-based microcavities under continuous-wave pumping. The chaotic behavior of the instability results in a strongly reduced spatial and temporal coherence and a significantly inhomogeneous density. Additionally, we show how the instability can be tamed by introducing a periodic potential so that condensation occurs in negative mass states, leading to largely improved coherence and homogeneity. These results pave the way to the exploration of long-range order in dissipative quantum fluids of light within a controlled platform.

Domaines: Optique / photonique

F. Baboux, D. de Bernardis, V. Goblot, V. Gladilin, C. Gomez, et al.. Unstable and stable regimes of polariton condensation. Optica, 2018, 5 (10), pp.1163. ⟨10.1364/OPTICA.5.001163⟩. ⟨hal-02353534⟩