Massively Multiplexed Submicron Particle Patterning in Acoustically Driven Oscillating Nanocavities

Abstract

Nanoacoustic fields are a promising method for particle actuation at the nanoscale, though THz frequencies are typically required to create nanoscale wavelengths. In this work, the generation of robust nanoscale force gradients is demonstrated using MHz driving frequencies via acoustic‐structure interactions. A structured elastic layer at the interface between a microfluidic channel and a traveling surface acoustic wave (SAW) device results in submicron acoustic traps, each of which can trap individual submicron particles. The acoustically driven deformation of nanocavities gives rise to time‐averaged acoustic fields which direct suspended particles toward, and trap them within, the nanocavi..