Excitations and superfluidity in non-equilibrium Bose-Einstein condensates of exciton-polaritons

We present a generic model for the description of non-equilibrium Bose-Einstein condensates, suited for the modelling of non-resonantly pumped polariton condensates in a semiconductor microcavity. The excitation spectrum and scattering of the non-equilibrium condensate with a defect are discussed. (C) 2007 Elsevier Ltd. All rights reserved.