Acoustic tweezing for both Rayleigh and Mie particles based on acoustic focused petal beams

摘要

Acoustic tweezers (ATs) have been extensively exploited in physics, biology, chemistry, and medical medicine. However, previous ATs are limited by complex designs and cumbersome configurations, and the stable manipulation of Mie particles remains challenging. Here, an AT based on acoustic focused petal beams (AFPBs) is proposed to realize 2D stable manipulations of both Rayleigh and Mie particles in water. The AFPBs are generated by artificial structure plates (ASPs) engraved with two kinds of discrete curved slits. It is found that the bright petals of AFPBs are flexibly modulated by arranging the sectors of curved slits on ASP, and the central zero-intensity region encircled by bright petals is increased with the number of petals. Then, the acoustic radiation forces of the AFPBs with 2 and 10 petals acting on the Rayleigh and Mie particles are further studied, respectively, and a force equilibrium position is found in both cases. Finally, two ASP samples are fabricated to experimentally verify the generations of AFPBs, and the 2D stable trappings and movements of both Rayleigh and Mie particles are realized by AFPBs. This miniaturized AT is beneficial to practical applications in material fabrication, drug delivery, and tissue engineering.