School of Physics & Astronomy, University of Glasgow, G12 8QQ Glasgow, United Kingdom.
College of Optical Sciences, University of Arizona, Tucson, Arizona 85721, USA.
Phys Rev Lett. 2019 Jul 26;123(4):044301. doi: 10.1103/PhysRevLett.123.044301.
Superradiant gain is the process in which waves are amplified via their interaction with a rotating body, examples including the evaporation of a spinning black hole and electromagnetic emission from a rotating metal sphere. In this Letter we elucidate how superradiance may be realized experimentally in the field of acoustics, and predict the possibility of nonreciprocally 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 acoustic superradiant amplification using existing technology.
超辐射增益是通过波与旋转体的相互作用来放大波的过程，例如旋转黑洞的蒸发和旋转金属球的电磁辐射。在这封信中，我们阐明了超辐射如何在声学领域中得到实验验证，并预测了通过在旋转吸收介质中传播带有轨道角动量的声束来实现非互易声束放大或吸收的可能性。我们讨论了使用现有技术实现声超辐射放大的可能几何形状。
