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arXiv · 1809.03489

Superradiant Amplification of Acoustic Beams via Medium Rotation

Daniele Faccio·Ewan M. Wright
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Abstract

Superradiant gain is the process in which waves are amplified via their interaction with a rotating body, examples including evaporation of a spinning black hole and electromagnetic emission from a rotating metal sphere. In this paper we elucidate theoretically how superradiance may be realized in the field of acoustics, and predict the possibility of non-reciprocally amplifying or absorbing acoustic beams carrying orbital angular momentum by propagating them through an absorbing medium that is rotating. We discuss a possible geometry for realizing the superradiant amplification process using existing technology.

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Daniele Faccio, Ewan M. Wright. 2018-09-08. Superradiant Amplification of Acoustic Beams via Medium Rotation. https://doi.org/10.1103/physrevlett.123.044301

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