Anomalous transport of excitons in Cu2O

Quite a number of experimental and theoretical work has been devoted last decade to the investigation of sonic nondiffusive transport of excitons in Cu2O. However, the Bose-Einstein condensation interpretation of this transport is controversial. In this paper we summarize the interpretation of the anomalous exciton transport in Cu2O via nonequilibrium phonon-assisted drag of excitons (phonon wind). We explain the intensity and temperature dependencies of the exciton transport and the nonlinearities under two-pulse and pulse & cw excitation and propose several experiments to check the predictions of the phonon wind model.