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Towards the observation of Hawking radiation in Bose--Einstein condensates

Carlos Barcelo·Stefano Liberati·Matt Visser
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Abstract

Acoustic analogues of black holes (dumb holes) are generated when a supersonic fluid flow entrains sound waves and forms a trapped region from which sound cannot escape. The surface of no return, the acoustic horizon, is qualitatively very similar to the event horizon of a general relativity black hole. In particular Hawking radiation (a thermal bath of phonons with temperature proportional to the ``surface gravity'') is expected to occur. In this note we consider quasi-one-dimensional supersonic flow of a Bose--Einstein condensate (BEC) in a Laval nozzle (converging-diverging nozzle), with a view to finding which experimental settings could magnify this effect and provide an observable signal. We identify an experimentally plausible configuration with a Hawking temperature of order 70 n K; to be contrasted with a condensation temperature of the order of 90 n K.

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Carlos Barcelo, Stefano Liberati, Matt Visser. 2001-10-06. Towards the observation of Hawking radiation in Bose--Einstein condensates. https://doi.org/10.1142/s0217751x0301615x

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