Miniature plasmonic wave plates

TL;DR

This paper introduces a novel method for creating miniature planar wave plates using surface plasmons, enabling precise polarization control without compromising optical coherence.

Contribution

It presents a general design approach for miniature plasmonic wave plates with elliptical gratings that can fully manipulate polarization states.

Findings

Successfully demonstrated a surface plasmon-based quarter wave plate

Maintained optical coherence during polarization manipulation

Enabled complete polarization control by shape tuning of elliptical gratings

Abstract

Linear birefringence, as implemented in wave plates, is a natural way to control the state of polarization of light. We report on a general method for designing miniature planar wave plates using surface plasmons. The resonant optical device considered here is a single circular aperture surrounded by an elliptical antenna grating. The difference in short and long axis of each ellipses introduces a phase shift on the surface plasmons which enables the realization of a quarter wave plate. Furthermore, the experimental results and the theoretical analysis show that the general procedure used does not influence the optical coherence of the polarization state and allows us to explore completely the surface of the unit Poincare sphere by changing only the shape of the elliptical grating.