Optical equilibrium for resonant particles induced by surface plasmons of two-dimensional materials

Abstract

The optomechanical interaction of a resonant particle with a current sheet, graphene for example, induced by its surface plasmon is investigated. It is predicted that stable equilibrium positions for the particle at finite distances from the sheet can be formed. For high-index dielectric particles the equilibria take place in a finite frequency range close to the Mie resonances. Thus, the excitation of resonances by the plasmon and their coupling to the sheet give rise to the strong repulsion, which competes against the usually prevailing attraction induced by the evanescent tail. The formation of purely optical stable equilibria for particles outside of waveguiding structures can find applications for particle propulsion, sorting, and in various systems that require particle isolation.