Analog Hawking radiation from an acoustic black hole in a flowing polariton superfluid

We theoretically study Hawking radiation processes from an analog acoustic black hole in a flowing superfluid of exciton-polaritons in a one-dimensional semiconductor microcavity. Polaritons are coherently injected into the microcavity by a laser pump with a suitably tailored spot profile. An event horizon with a large analog surface gravity is created by inserting a defect in the polariton flow along the cavity plane. Experimentally observable signatures of the analog Hawking radiation are identified in the scattering of phonon wave packets off the horizon, as well as in the spatial correlation pattern of quantum fluctuations of the polariton density. The potential of these tabletop optical systems as analog models of gravitational physics is quantitatively confirmed by numerical calculations using realistic parameters for state-of-the-art devices.