High Transmission in 120-degree Sharp Bends of Inversion-symmetric and Inversion-asymmetric Photonic Crystal Waveguides
arXiv:2310.17487 · doi:10.1038/s41467-025-56020-8
Abstract
Bending loss is one of the serious problems for constructing nanophotonic integrated circuits. Recently, many works reported that valley photonic crystals (VPhCs) enable significantly high transmission via 120-degree sharp bends. However, it is unclear whether the high bend-transmission results directly from the valley-photonic effects, which are based on the breaking of inversion symmetry. In this study, we conduct a series of comparative numerical and experimental investigations of bend-transmission in various triangular PhCs with and without inversion symmetry and reveal that the high bend-transmission is solely determined by the domain-wall configuration and independent of the existence of the inversion symmetry. Preliminary analysis of the polarization distribution indicates that high bend-transmissions are closely related to the appearance of local topological polarization singularities near the bending section. Our work demonstrates that high transmission can be achieved in a much wider family of PhC waveguides, which may provide novel designs for low-loss nanophotonic integrated circuits with enhanced flexibility and a new understanding of the nature of valley-photonics
arXiv comment15 pages, 7 figures, and 1 table & Supplementary information (18 pages, 15 figures and 1 table). Submitted to Nature Communication
References in corpus (22)
- Berry Phase Effects on Electronic Properties
- Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides
- Topological Photonics
- Possible Realization of Directional Optical Waveguides in Photonic Crystals with Broken Time-Reversal Symmetry
- Valley contrasting physics in graphene: magnetic moment and topological transport
- The Valley Hall Effect in MoS2 Transistors
- Analogs of quantum Hall effect edge states in photonic crystals
- All-Si Valley-Hall Photonic Topological Insulator
- Deterministic photon-emitter coupling in chiral photonic circuits
- A Silicon-on-Insulator Slab for Topological Valley Transport
- Topological Phases in Two-Dimensional Materials: A Brief Review
- Direct Observation of Valley-polarized Topological Edge States in Designer Surface Plasmon Crystals
- Valley-contrasting orbital angular momentum in photonic valley crystals
- Valley-protected backscattering suppression in silicon photonic graphene
- Polarization engineering in photonic crystal waveguides for spin-photon entanglers
- Pseudospin-valley coupled edge states in a photonic topological insulator
- Observation of strong backscattering in valley-Hall photonic topological interface modes
- Quantifying the robustness of topological slow light
- Experimental demonstration of topological slow light waveguides in valley photonic crystals
- GaAs valley photonic crystal waveguide with light-emitting InAs quantum dots
- Evolution of topological edge modes from honeycomb photonic crystals to triangular-lattice photonic crystals
- The stability of polarisation singularities in disordered photonic crystal waveguides