Acoustic lateral recoil force and stable lift of anisotropic particles

Abstract

Acoustic manipulation of small particles is important for various applications, particularly in the life sciences, yet understanding higher-order acoustic forces and torques on larger, nonspherical particles has remained unexplored. This work reveals two interesting phenomena: a lateral acoustic recoil force, and a stable acoustic lift for an anisotropically shaped particle in a sound-wave field. The authors' discovery offers fresh functionalities for acoustic manipulation and sorting of anisotropic particles, including biomolecules and cells.