Talbot effect for exciton-polaritons

We demonstrate formation of a Talbot carpet for hybrid light-matter waves - Bose-Einstein condensate of exciton-polaritons formed in a quantum well inside a semiconductor microcavity. The Talbot effect is created by loading the condensate into a microstructured periodic array of mesa traps which act as sources of the polariton waves in the plane of the quantum well. The spatial distribution of polaritons outside the mesas mimics the near-field diffraction of a monochromatic wave on a periodic grating with the characteristic spatial period determined by the polariton wavelength. Despite the lossy nature of the polariton system, the Talbot pattern persists for the distances exceeding the transverse dimension of the mesas by an order of magnitude.