Observation of the spin-based plasmonic effect in nanoscale structures

TL;DR

This paper reports the experimental observation of spin-dependent plasmonic effects in nanoscale structures, revealing polarization-sensitive phenomena and vortex modes driven by geometric phase interactions.

Contribution

It demonstrates the first observation of spin-based surface plasmon effects and polarization-sensitive focusing in nanoscale plasmonic structures.

Findings

Spin-dependent near-field intensity distribution observed

Presence of a geometric phase affecting plasmonic behavior

Demonstration of polarization-sensitive focusing

Abstract

Observation of surface-plasmon phenomena that are dependent upon the handedness of the circularly polarized incident light (spin) is presented. The polarization-dependent near-field intensity distribution obtained in our experiment is attributed to the presence of a geometric phase arising from the interaction of light with an anisotropic and inhomogeneous nanoscale structure. A near-field vortex surface mode with a spin-dependent topological charge was obtained in a plasmonic microcavity. The remarkable phenomenon of polarization-sensitive focusing in a plasmonic structure was also demonstrated.