Room temperature ballistic transport of exciton-polaritons in a one-dimensional whispering gallery microcavity

Abstract In this work, we report the experimental observation of the ballistic transport of condensed exciton-polaritons at room temperature in a one-dimensional whispering-gallery microcavity. Such coherent transport, initiated by the pronounced inter-particle interactions of polaritons, leads to the generation of two symmetric emission beams in the momentum (angular) space. By means of spatially filtered angle-resolved photoluminescence imaging spectroscopy, we were able to identify their origin and successfully rationalize these observations using the potential energy-to-kinetic energy conversion picture. The energy-dependent emission linewidth, as well as TM to TE inter-mode scattering, have also been discussed.