Direct Observation of Nanoscale Chiral Light-Matter Interactions Governed by Optical Chirality

Optical chirality has been proposed as the fundamental quantity governing chiral light-matter interactions, but direct experimental verification has remained elusive. Here we realize an optical field with spatially modulated optical chirality and nearly uniform electric energy density, and provide the first direct experimental verification that optical chirality governs nanoscale chiral light-matter interactions. A single chiral nanoparticle exhibits a differential response that follows the spatial modulation of optical chirality, whereas no modulation is observed for an achiral nanoparticle. Electromagnetic simulations further demonstrate the feasibility of enantioselective optical trapping through experimentally achievable chiral optical forces.