Optimization and robustness of topological corner state in second-order topological photonic crystal

Abstract

The second-order topological photonic crystal with 0D corner state provides a new way to investigate cavity quantum electrodynamics and develop topological nanophotonic devices with diverse functionalities. Here, we report on the optimization and robustness of topological corner state in the second-order topological photonic crystal both in theory and in experiment. The topological nanocavity is formed based on the 2D generalized Su-Schrieffer-Heeger model. The quality factor of corner state is optimized theoretically and experimentally by changing the gap between two photonic crystals or just modulating the position or size of the airholes surrounding the corner. The fabricated quality factors are further optimized by the surface passivation treatment which reduces surface absorption. A maximum quality factor of the fabricated devices is about 6000, which is the highest value ever reported for the active topological corner state. Furthermore, we demonstrate the robustness of corner state against strong disorders including the bulk defect, edge defect, and even corner defect. Our results lay a solid foundation for the further investigations and applications of the topological corner state, such as the investigation of strong coupling regime and the development of optical devices for topological nanophotonic circuitry.

13 pages, 9 figures

References in corpus (13)

• Topological Photonics
• Photonic Analogue of Two-dimensional Topological Insulators and Helical One-Way Edge Transport in Bi-Anisotropic Metamaterials
• Scheme to Achieve Silicon Topological Photonics
• Higher-order topological insulators and semimetals on the breathing Kagome and pyrochlore lattices
• Visualization of higher-order topological insulating phases in two-dimensional dielectric photonic crystals
• Direct observation of corner states in second-order topological photonic crystal slabs
• Novel Topological Phase with Zero Berry Curvature
• Photonic crystal nanocavity based on a topological corner state
• Low-threshold topological nanolasers based on second-order corner state
• Cavity Quantum Electrodynamics with Second-Order Topological Corner State
• Coupled cavity-waveguide system based on topological corner state and edge state
• Enhanced Strong Interaction between Nanocavities and p-shell Excitons Beyond the Dipole Approximation
• Mode identification of high-quality-factor single-defect nanocavities in quantum dot-embedded photonic crystals

Cited by in corpus (4)

• Topological photonic crystals: physics, designs and applications
• A brief review of topological photonics in one, two, and three dimensions
• Higher-order topological phases in crystalline and non-crystalline systems: a review
• Remote control of spin polarization of topological corner states