Chiral near fields generated from plasmonic optical lattices

Abstract

Plasmonic fields are usually considered non-chiral because of the transverse\nmagnetic polarization of surface plasmon modes. We however show here that an\noptical lattice created from the intersection of two coherent surface plasmons\npropagating on a smooth metal film can generate optical chirality in the\ninterfering near field. We reveal in particular the emergence of plasmonic\npotentials relevant to the generation of near-field chiral forces. This draws\npromising perspectives for performing enantiomeric separation schemes within\nthe near field.\n