Cavity polaritons are mixed exciton-photon states arising from the strong coupling regime between excitons confined in quantum wells and photons confined in an optical microcavity. They are bosonic quasi-particules with a very small effective: they offer the possibility to investigate the physics of Bose condensates in a solid state system. Polariton condensates are out of equilibrium dynamical condensates, with weak interactions mediated by their excitonic part. They have a pseudo-spin which can be optically addressed.
After a general introdution to cavity polaritons, I will describe recent experiments performed on one dimensional cavities. We have generated polariton condensates which can propagate over macroscopic distances while preserving their spatial coherence. We have shown that these condensates can be optically manipulated, coupled through a controlled tunnel barrier or trapped in a controlled way. Interactions play a key role in these experiments.
These results open the way toward the realization of new optical circuits based on the propagation and manipulation of polariton condensates.
“Spontaneous formation and optical manipulation of extended polariton condensates”, E. Wertz, L. Ferrier, D. Solnyshkov, R. Johne, D. Sanvitto, A. Lemaître, I. Sagnes, R. Grousson, A.V. Kavokin, P. Senellart, G. Malpuech and J. Bloch, Nature Physic 6, 860 (2010).
«Interactions in Confined Polariton Condensates », L. Ferrier, E. Wertz, R. Johne, D.D. Solnyshkov, P. Senellart, I. Sagnes, A. Lemaître, G. Malpuech, and J. Bloch, Phys. Rev. Lett. 106, 126401 (2011)