An acoustic black hole in a stationary hydrodynamic flow of microcavity polaritons

摘要

We report an experimental study of superfluid hydrodynamic effects in aone-dimensional polariton fluid flowing along a laterally patternedsemiconductor microcavity and hitting a micron-sized engineered defect. At highexcitation power, superfluid propagation effects are observed in the polaritondynamics, in particular, a sharp acoustic horizon is formed at the defectposition, separating regions of sub- and super-sonic flow. Our experimentalfindings are quantitatively reproduced by theoretical calculations based on ageneralized Gross-Pitaevskii equation. Promising perspectives to observeHawking radiation via photon correlation measurements are illustrated.