Plasmonic Route to Reconfigurable Polarization Optics

TL;DR

This paper introduces a plasmonic polarization router that uses nanohole arrays to reconfigure and control light polarization states, enabling advanced polarization multiplexing and signal processing capabilities.

Contribution

It presents a novel nanostructure design that manipulates surface plasmon polaritons to achieve reconfigurable polarization control and multiple focused beams with different polarizations.

Findings

Device can reconfigure input polarization to various states.

Simultaneous generation of multiple polarized focused beams.

Potential applications in polarization multiplexing and signal processing.

Abstract

Surface plasmon polariton (SPP) as a bounded mode on a metal/dielectric interface intrinsically has a definite transverse magnetic (TM) polarization that usually lacks further manipulations. However, the in-plane longitudinal components of SPP field can produce versatile polarization states when two orthogonal propagating SPP interfere with each other. Here, we demonstrated a plasmonic polarization router by designing appropriate nanohole arrays that can selectively scatter the interfered SPP fields to desired light beams. It is well proved that our device is able to reconfigure a certain input polarization to all kinds of states with respect to a scattered light. Accompanied with a composite phase modulation by diffractions, multiple focusing beams with different polarization states are simultaneously achieved, promising the possibility in polarization multiplexing and related signal processing. Our design offers a new route for achieving full control of the optical polarizations as well as the optical spin-orbital interactions.