Engineering chiral light--matter interaction in photonic crystal waveguides with slow light

TL;DR

This paper presents the design of photonic crystal waveguides with glide-plane symmetry that enable strong, chiral light-matter interactions even with slow light, facilitating efficient quantum emitter integration.

Contribution

It introduces a novel glide-plane-symmetric waveguide design that achieves high Purcell enhancement and chirality in slow light regimes, enabling near-unity directional coupling.

Findings

Achieves slow-down factors up to 100 with maintained chirality.

Demonstrates near-unity directional beta-factors for various emitter positions.

Develops an efficient mode adapter for integration with standard waveguides.

Abstract

We design photonic crystal waveguides with efficient chiral light--matter interfaces that can be integrated with solid-state quantum emitters. By using glide-plane-symmetric waveguides, we show that chiral light-matter interaction can exist even in the presence of slow light with slow-down factors of up to $100$ and therefore the light--matter interaction exhibits both strong Purcell enhancement and chirality. This allows for near-unity directional $\beta$-factors for a range of emitter positions and frequencies. Additionally, we design an efficient mode adapter to couple light from a standard nanobeam waveguide to the glide-plane symmetric photonic crystal waveguide. Our work sets the stage for performing future experiments on a solid-state platform.