Optical sorting of dielectric Rayleigh spherical particles with scattering and standing waves

An all optical method for dielectric Rayleigh particle sorting possesses significant advantages. Here, we describe an approach that applies optical scattering forces to translate varied sized particles differentially from a surface followed by the introduction of an optical standing wave to maintain and tighten the positional tolerance of the differentiated particles in the medium. Numerical simulation demonstrates the workability of this scheme; which is highly dependent on Brownian forces typically dominant at this length scale. It also shows the significant impact of temperature and medium viscosity on the operation of this technique.