Large-Angle Bending Transport of Microparticles by Acoustic Half-Bessel Beams

TL;DR

This paper introduces acoustic Half-Bessel beams for micromanipulation, enabling microparticles to follow large-angle, robust bending trajectories exceeding 90 degrees, surpassing the capabilities of traditional Airy beams.

Contribution

It presents a novel use of acoustic Half-Bessel beams for large-angle microparticle transport, expanding the potential of acoustic micromanipulation techniques.

Findings

Achieved microparticle bending angles exceeding 90 degrees.

Demonstrated robustness of particle transport in complex scattering environments.

Compared performance favorably to Airy beam-based methods.

Abstract

Conventional microparticle transports by light or sound are realized along a straight line. Recently, this limit has been overcome in optics as the growing up of the self-accelerating Airy beams, which are featured by many peculiar properties, e.g., bending propagation, diffraction-free and self-healing. However, the bending angles of Airy beams are rather small since they are only paraxial solutions of the two-dimensional (2D) Helmholtz equation. Here we propose a novel micromanipulation by using acoustic Half-Bessel beams, which are strict solutions of the 2D Helmholtz equation. Compared with that achieved by Airy beams, the bending angle of the particle trajectory attained here is much steeper (exceeding 90o). The large-angle bending transport of microparticles, which is robust to complex scattering environment, enables a wide range of applications from the colloidal to biological sciences.