Liu Jie, Liang Li, Xu Minhan, Poo Yin
Opt Express. 2025 Mar 24;33(6):13887-13894. doi: 10.1364/OE.551936.
We presented the findings on the coexistence of quantum anomalous Hall (QAH) and valley Hall (VH) phases within an identical photonic gap in a hexagonal photonic crystal. The synergistic effect of broken time-reversal symmetry (BTRS) and broken rotation symmetry (BRS) unbuckles the triple-degenerated points at K and K' points, which is crucial for the coexistence of multiple topological phases. The competition of BTRS and BRS adjusts the transition of topological phases. It has been verified that the configuration mainly exhibits the QAH phase through bulk-edge correspondence. The VH phase becomes apparent only after the QAH phase has disappeared. As an application, a circulator with six ports has been further proposed. Our study offers insights into the interplay among photonic topological phases, highlighting potential applications in robust waveguiding and photonic on-chip devices.
我们展示了在六角形光子晶体的同一光子带隙内量子反常霍尔（QAH）相和谷霍尔（VH）相共存的研究结果。时间反演对称性破缺（BTRS）和旋转对称性破缺（BRS）的协同效应解开了K和K'点处的三重简并点，这对于多个拓扑相的共存至关重要。BTRS和BRS的竞争调节了拓扑相的转变。通过体边对应已证实该结构主要呈现QAH相。VH相仅在QAH相消失后才变得明显。作为一种应用，进一步提出了一种六端口环行器。我们的研究为光子拓扑相之间的相互作用提供了见解，突出了其在稳健波导和光子片上器件中的潜在应用。
