Potential of theoretical approach and T-matrix method for designing numerical acoustical tweezers toolbox

Abstract

Partial-wave series solution and T-matrix method (TMM) could be used for computations of radiation force and torque exerted on objects from an acoustic Bessel beam (ABB) with arbitrary order and location. The radiation force and torque in Bessel beams could be expressed in terms of incident and scattered coefficients which could be obtained analytically based on the multipole expansion method [Gong et al., J. Acoust. Soc. Am. 141, EL574–578 (2017)].The investigation of radiation force and torque could be used to design numerical acoustical tweezers toolbox that may manipulate particles and cells as expected, showing potential in physical chemistry, biomedicine, and so on. This work claims the possibility and potential of the theoretical and numerical methods for acoustical tweezers toolbox which could trap, pull, push, and rotate targets of different shapes and components. Both the progressive and (quasi)standing Bessel beams will be considered. In addition, beams which could be expanded in terms of basis functions, for example, Gaussian beams, could also be included in this numerical toolbox. The numerical toolbox of acoustical tweezers could help to guide experimental set-ups. [Work supported by NSFC (W.L. and Z.G.), ONR (P.L.M.), and China Scholarship Council (Z.G.).]