Computational analysis of optical trapping of transparent and reflecting micron-sized spherical particles

Abstract

In the ray-optics regime, we calculated the radial and axial force field on a micron-sized spherical particle in an optical levitation trap. The momentum change in the photon-stream path of tightly focused incident laser beam causes the calculated force field in the optical trap. The computational results for the force field are compared with the literature and a good agreement is obtained. Utilizing the benchmarked force field, the optical trapping dynamics of (i) a transparent spherical particle with continuous-wave 𝑇𝑇𝑇𝑇𝑇𝑇00 Gaussian beam and (ii) a reflecting spherical particle with continuous-wave 𝑇𝑇𝑇𝑇𝑇𝑇01 ∗ Laguerre-Gaussian beam under various conditions are simulated in Matlab.