title: Acoustic black hole in a stationary hydrodynamic flow of microcavity polaritons.
abstract: We report an experimental study of superfluid hydrodynamic effects in a one-dimensional polariton fluid flowing along a laterally patterned semiconductor microcavity and hitting a micron-sized engineered defect. At high excitation power, superfluid propagation effects are observed in the polariton dynamics; in particular, a sharp acoustic horizon is formed at the defect position, separating regions of sub- and supersonic flow. Our experimental findings are quantitatively reproduced by theoretical calculations based on a generalized Gross-Pitaevskii equation. Promising perspectives to observe Hawking radiation via photon correlation measurements are illustrated.
authors: Laboratoire de Photonique et de Nanostructures, LPN/CNRS, Route de Nozay, 91460 Marcoussis, France.
authors: H S
authors: HS
authors: Nguyen
authors: Dipartimento di Fisica, Università di Pavia, via Bassi 6, I-27100 Pavia, Italy.
authors: D
authors: D
authors: Gerace
authors: INO-CNR BEC Center and Dipartimento di Fisica, Università di Trento, I-38123 Povo, Italy.
authors: I
authors: I
authors: Carusotto
authors: NNL, Istituto Nanoscienze - CNR, Via Arnesano, 73100 Lecce, Italy.
authors: D
authors: D
authors: Sanvitto
authors: Laboratoire de Photonique et de Nanostructures, LPN/CNRS, Route de Nozay, 91460 Marcoussis, France.
authors: E
authors: E
authors: Galopin
authors: Laboratoire de Photonique et de Nanostructures, LPN/CNRS, Route de Nozay, 91460 Marcoussis, France.
authors: A
authors: A
authors: Lemaître
authors: Laboratoire de Photonique et de Nanostructures, LPN/CNRS, Route de Nozay, 91460 Marcoussis, France.
authors: I
authors: I
authors: Sagnes
authors: Laboratoire de Photonique et de Nanostructures, LPN/CNRS, Route de Nozay, 91460 Marcoussis, France.
authors: J
authors: J
authors: Bloch
authors: Laboratoire de Photonique et de Nanostructures, LPN/CNRS, Route de Nozay, 91460 Marcoussis, France.
authors: A
authors: A
authors: Amo