Polariton acceleration in a microcavity wedge - art. no. 081303

We report an experimental evidence of the acceleration of exciton-polariton s propagating in-plane of a semiconductor microcavity. The acceleration is achieved due to the gradient of the thickness of the cavity and results fro m the reciprocal space filtering effect of the cavity. The wave packet prop agating in the cavity plane is constantly filtered by the cavity eigenmode that shifts towards larger wave vectors as the cavity width increases. The decay time of the emission of light by the propagating polaritons increases as one approaches the anticrossing region. We show that it is a consequenc e of the elastic scattering of the polaritons. The spatial size of propagat ing polariton packet decreases with time due to the same effect.