Spatial Resonator Solitons Based on Different Semiconductor Nonlinearities

Optical bistability and bright and dark resonator solitons exist in semiconductor resonator at room temperature [CO. Weis and Ye. Larionova, Rep. Prog. Phys. 70 (2007) 255-335], with the usual semiconductor nonlinearity. At low temperature in the strong coupling regime between quantum well excitons and the optical field in a semiconductor microcavity the nonlinearities are strong and based on "polariton nonlinearity". The strong coupling results in a quasi-particle "exciton-polariton" which gives access to positive and negative reactive and dissipative optical nonlinearities, as opposed to the usual room temperature semiconductor nonlinearities possessing essentially only one sign. The type of nonlinearity and the properties of solitons can be varied widely by the detuning between the photon- and exciton resonances. We show for the first time experimentally the existence of patterns, bright and dark solitons based on polariton nonlinearity.