Acoustic Virtual Vortices with Tunable Orbital Angular Momentum for Trapping of Mie Particles

Paper: Acoustic vortices can transfer angular momentum and trap particles. Here, we show that particles trapped in airborne acoustic vortices orbit at high speeds leading to dynamic instability and ejection. We demonstrate stable trapping inside acoustic vortices by generating sequences of short-pulsed vortices of equal helicity but opposite chirality. This produces a “virtual vortex“ with an orbital angular momentum that can be tuned ind