Creating interparticle forces with sound

Although less widely used then their optical counterparts, acoustic forces can be used to meaningfully control the assembly of particles at a variety of scales. In addition to the well known single particle gradient force, there is also an interparticle force which becomes comparable to other forces when the particle is of order one wavelength in size. As this size regime prevents the use of simple analytical models, we will present a robust numerical model which allows us to study these effects in numerical simulations. With it we elucidate some of the interesting dynamics present in multi-body acoustophoretic systems and demonstrate stable configurations in large groups.