Enantioselection and chiral sorting of single microspheres using optical pulling forces

Abstract

We put forward a novel, twofold scheme that enables at the same time all-optical enantioselection and sorting of single multipolar chiral microspheres based on optical pulling forces exerted by two non-collinear, nonstructured, circularly-polarized light sources. Our chiral resolution method can be externally controlled by varying the angle between their incident wavevectors, allowing for a fine-tuning of the range of chiral indices for enantioselection. Enantioselectivity is achieved by choosing angles such that only particles with the same handedness of the light sources are pulled. This proposal allows one to achieve all-optical sorting of chiral microspheres with arbitrarily small chiral parameters, thus outperforming current optical methods.