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arXiv · 1904.00684

Superradiant scattering in fluids of light

Angus Prain·Calum Maitland·Daniele Faccio·Francesco Marino
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Abstract

We theoretically investigate the scattering process of Bogoliubov excitations on a rotating photon-fluid. Using the language of Noether currents we demonstrate the occurrence of a resonant amplification phenomenon, which reduces to the standard superradiance in the hydrodynamic limit. We make use of a time-domain formulation where superradiance emerges as a transient effect encoded in the amplitudes and phases of propagating localised wavepackets. Our findings generalize previous studies in quantum fluids to the case of a non-negligible quantum pressure and can be readily applied also to other physical systems, in particular atomic Bose-Einstein condensates. Finally we discuss ongoing experiments to observe superradiance in photon fluids, and how our time domain analysis can be used to characterise superradiant scattering in non-ideal experimental conditions.

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gr-qccond-mat.quant-gasphysics.optics

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Angus Prain, Calum Maitland, Daniele Faccio, Francesco Marino. 2019-04-01. Superradiant scattering in fluids of light. https://doi.org/10.1103/physrevd.100.024037

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