Observation of backscattering-immune chiral electromagnetic modes without time reversal breaking

TL;DR

This paper demonstrates a method to achieve backscattering-immune chiral electromagnetic modes in nonmagnetic dielectric photonic crystals, enabling robust light transport without breaking time-reversal symmetry.

Contribution

It introduces a novel approach to realize robust, backscattering-immune chiral modes in dielectric photonic systems without external magnetic fields.

Findings

Chiral guided modes are immune to scattering from inserted metal or dielectric patches.

Microwave experiments confirm the robustness of these modes.

Numerical simulations support the experimental results.

Abstract

A strategy is proposed to realize robust transport in time reversal invariant photonic system. Using numerical simulation and microwave experiment, we demonstrate that a chiral guided mode in the channel of a three-dimensional dielectric woodpile photonic crystal is immune to the scattering of a square patch of metal or dielectric inserted to block the channel. The chirality based robust transport can be realized in nonmagnetic dielectric materials without any external field.