Magnetized spiral chains of plasmonic ellipsoids for one-way optical waveguides

TL;DR

This paper demonstrates that a spiral chain of magnetized plasmonic ellipsoids can create one-way optical waveguides by combining Faraday rotation and structural chirality, leading to non-reciprocal light propagation.

Contribution

It introduces a novel design of spiral chains of plasmonic ellipsoids under magnetic fields that enhances non-reciprocal optical waveguiding through combined effects.

Findings

Achieves one-way light propagation in four frequency bands

Enhances non-reciprocity via interplay of Faraday rotation and spiral geometry

Demonstrates potential for integrated optical isolators

Abstract

When a linear chain of plasmonic nano-particles is subject to longitudinal magnetic field, it exhibits optical Faraday rotation. If the magnetized nano-particles are plasmonic ellipsoids arranged as a spiral chain, the interplay between the Faraday rotation and the geometrical spiral rotation (structural chirality) can strongly enhance non-reciprocity. This interplay forms a waveguide that permits one way propagation only, within four disjoint frequency bands; two bands for each direction.