Liu Zhenzhen, Wei Guochao, Wu Huizhou, Xiao Jun-Jun
College of Electronic and Information Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China.
Shenzhen Engineering Laboratory of Aerospace Detection and Imaging, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China.
Nanophotonics. 2023 Jul 14;12(17):3481-3490. doi: 10.1515/nanoph-2023-0311. eCollection 2023 Aug.
The presence of gauge flux enabled by positive and negative hopping amplitude can lead to Möbius bands, which was recently demonstrated in both realistic acoustic and photonic lattices, twisted at = . Here, we show that the artificial gauge flux configuration can be achieved by exploiting the interactions between photonic and orbital-like fundamental modes in circular and peanut-shaped waveguides, respectively. By manipulating the interplay between the gauge fields and the crystal symmetry, we show that breaking the primitive translation symmetry through lattice site dimerization and deformation can cause the original Dirac semimetal phase, characterized by a four-fold Dirac point at the Brillouin zone center, to transform into various topological phases. The designed photonic waveguide array supports topological phases such as Möbius insulator and Weyl-like semimetal phases. Noticeably different to the existing cases, we explicitly show that the twisting Möbius bands cross each other at = 0 due to the lattice gauging with alternating sign, which results in distinct beam dynamics excitation. We also present Weyl-like flat-band edge states in such photonics waveguide arrays. Our results suggest that such - hybridized photonic waveguide array servers as a convenient and flexible platform for studying topological physics, particularly in simulating the effects of gauge field in alternative configuration.
由正负跳跃幅度实现的规范通量的存在可导致莫比乌斯带，这一点最近在实际的声学和光子晶格中都得到了证明，其在 = 处发生扭曲。在这里，我们表明，可以分别通过利用圆形和花生形波导中光子与轨道状基本模式之间的相互作用来实现人工规范通量配置。通过操纵规范场与晶体对称性之间的相互作用，我们表明，通过晶格位点二聚化和变形打破原始平移对称性会导致原始狄拉克半金属相（其特征是在布里渊区中心有一个四重狄拉克点）转变为各种拓扑相。所设计的光子波导阵列支持诸如莫比乌斯绝缘体和类外尔半金属相等拓扑相。与现有情况明显不同的是，我们明确表明，由于具有交替符号的晶格规范，扭曲的莫比乌斯带在 = 0 处相互交叉，这导致了独特的光束动力学激发。我们还在此类光子波导阵列中展示了类外尔平带边缘态。我们的结果表明，这种 - 杂化光子波导阵列可作为研究拓扑物理的便捷灵活平台，特别是在模拟替代配置中规范场的效应方面。
