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arXiv · 1410.0238

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

H. S. Nguyen·D. Gerace·I. Carusotto·D. Sanvitto·E. Galopin·A. Lemaître·I. Sagnes·J. Bloch·A. Amo
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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 super-sonic 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.

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H. S. Nguyen, D. Gerace, I. Carusotto, D. Sanvitto, E. Galopin, A. Lemaître, I. Sagnes, J. Bloch, A. Amo. 2014-10-01. An acoustic black hole in a stationary hydrodynamic flow of microcavity polaritons. https://doi.org/10.1103/physrevlett.114.036402

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