Dynamics Landscape for Acoustic Superradiance

Abstract

We analyze the behaviour of acoustic vortex beams interacting with rotating, fluid-saturated porous materials. Regions of the parameter space that exhibit distinct dynamical features are identified, with a focus on features that are relevant to the characterization of rotational superradiance. We discuss the similarities and differences between two recent proposals to observe acoustic superradiance with rotating, air-saturated sound absorbers. Finally, theoretical predictions for macroscopic acoustic scattering, obtained by averaging over interactions between the fluid and the porous material at the microscopic level, are compared with predictions of the first-Born approximation.

6 pages, 2 figures

References in corpus (2)

• Detecting Rotational Superradiance in Fluid Laboratories
• Superradiant Amplification of Acoustic Beams via Medium Rotation

Cited by in corpus (3)

• The next generation of analogue gravity experiments
• Penrose Superradiance in Nonlinear Optics
• Superradiant scattering of orbital angular momentum beams