Experimental investigation of multiple-particle patternbased on one-dimensional grating resonance field br

Manipulation of particles by ultrasonic waves is a primary technique in the fields of precisionmanufacturing, materials engineering, and in vitro diagnosis, since it can control the motion of objects in thesound field in a contactless and noninvasive manner. In general, the free sound field, such as the focused fieldand the plane wave generated by a single transducer can only manipulate a single particle. While the complexfield generated by a transducer array should be actuated by a complex electric control system, which makes themanipulation device expensive and cumbersome. Thus, modulated acoustic field for particle manipulation is stillneeded. Here, we experimental realize a one-dimensional acoustic grating to tune sound fields for the parallelpattern of multiple particles. The physical mechanism is that due to the resonance coupling between theperiodic diffraction wave on the surface of the acoustic grating and the Fabry-Perot resonant sound field in theacoustic grating slit, a periodical gradient sound field on the surface of the acoustic grating is induced. Then,particles in the periodical gradient sound field can be trapped in two stable positions in one period of thegrating. These concepts and realizations of particle patterns in the acoustic grating pave the way forimplementing the parallel manipulation of particles in acoustic manipulation technologies