Acoustic vortices in inhomogeneous media

Abstract

We observe a series of unstable and dynamic behaviors of acoustic vortices propagating in stratified inhomogeneous media. These behaviors include bending, stretching, distorting, focusing, and untwisting of the vortices, migration of singular points, and reversal of energy flux and angular momentum. We gain insight into how these behaviors result from the stratification. The results will be useful for applications of acoustic vortices in communication and particle manipulations in inhomogeneous media such as oceans and biomedical tissues. Our work opens up the study of the propagation of acoustic vortices in complex media.