Broadband and lossless lithium niobate valley photonic crystal waveguide

• 作者: Rui Ge Xiongshuo Yan Yuping Chen Xianfeng Chen
• 来源期刊: 中国光学快报（英文版）
• 年，卷（期）: 2021,（6）
• 所属期刊栏目: Special Issue on Lithium Niobate Based Photonic Devices
• 页码范围: 72-75
• 页数: 4页
• 语种: 英文
• DOI: 10.3788/COL202119.060014

摘要

We investigate the influences of structure parameters and interface shapes on the bandwidth of the edge state of lithium niobate valley photonic crystals.By increasing the size difference of two air holes in the same unit cell,we find that the bandwidth of the lossless nontrivial edge state possesses a peak value of 0.0201[a/λ],which can be used to construct broadband valley photonic crystal waveguides.Mode field distributions verify that the waveguide is robust against sharp bends and exhibits chirality.When the unit cell is arranged in a bearded interface with the top and bottom components showing negative and positive valley Chern numbers,respectively,we find that the lithium niobate valley photonic crystal is more likely to exhibit a lossless edge state,which is difficult to be realized in valley waveguides with low refractive index materials.This work can provide guidance on the design of the high-performance topological waveguide.