A topological photonic ring-resonator for on-chip channel filters

TL;DR

This paper introduces a topologically protected ring-resonator in valley photonic crystals on silicon, demonstrating unidirectional, defect-robust transmission for integrated photonic filtering applications.

Contribution

It presents a novel topological ring-resonator design in valley photonic crystals, fabricated on silicon, with demonstrated robustness and functionality as on-chip filters.

Findings

Unidirectional transmission confirmed in the resonator.

Robustness against structural defects demonstrated.

Effective as notch and channel-drop filters.

Abstract

A topologically protected ring-resonator formed in valley photonic crystals is proposed and fabricated on a silicon slab. The unidirectional transmission and robustness against structure defects of its resonant modes are illustrated. Coupled with topological waveguides, the topological ring is functioned as notch and channel-drop filters. The work opens up a new avenue for developing advanced chip-integrated photonic circuits with attributes of topological photonics.