Optical Tweezers Toolbox: full dynamics simulations for particles of all sizes

摘要

Simulation of optical tweezers involves the calculation of optical and non-optical forces and torques, modelling the Brownian motion of the particle and combining these components to calculate the overall dynamics of the system. Here we describe two new toolboxes: an improved optical force/torque calculation toolbox and a full dynamics simulation toolbox which combines all t he individual parts to simplify the process of calculating particle dynamics. The new toolbox will provide functions for simulating particle dynamics, estimating trap stiffness and calculating trap depths. The toolbox will be able to calculate optical forces/torques in different regimes including the geometric optics limit, Rayleigh limit, and intermediate regime with Vector Spherical Wave Functions/T-matrix,VSWF/T-matrix. Discrete Dipole Approximation. DDA, and the Final Difference Time Domain method, FDTD. Using these tools, it is possible to model different types of trapping configurations that can be used to study motile particles held in optical tweezers.