Confined one-way mode at magnetic domain wall for broadband high-efficiency one-way waveguide, splitter and bender

TL;DR

This paper demonstrates a novel magnetic domain wall-based one-way photonic mode enabling high-efficiency, broadband, and robust waveguiding components like splitters and benders, with magnetic control for reconfigurability.

Contribution

It introduces a well-confined one-way mode at magnetic domain walls for integrated photonics, enabling simple, high-performance, and tunable waveguide components.

Findings

High-efficiency, broadband, reflection-free waveguides achieved.

Splitter and bender structures can be transformed via magnetic control.

Robustness against disorder demonstrated.

Abstract

We find the one-way mode can be well-confined at the magnetic domain wall by the photonic bandgap of gyromagnetic bulk material. Utilizing the well-confined one-way mode at the domain wall, we demonstrate the photonic one-way waveguide, splitter and bender can be realized with simple structures, which are predicted to be high-efficiency, broadband, frequency-independent, reflection-free, crosstalk-proof and robustness against disorder. Additionally, we find that the splitter and bender in our proposal can be transformed into each other with magnetic control, which may have great potential applications in all photonic integrated circuit.