Topological photonic crystals are photonic versions of electronic topological crystals that show a topological property in electronic band structure. At the interface between two different topological photonic crystals, a topologically protected local...
Topological photonic crystals are photonic versions of electronic topological crystals that show a topological property in electronic band structure. At the interface between two different topological photonic crystals, a topologically protected localized edge state can be formed. Using this edge state, we can make a stable waveguide mode that is robust to crystal defects caused by a fabrication error. Here, we calculate a topological whispering gallery mode with 1.3 ㎛ wavelength by connecting the waveguide mode, and show numerically by finite-difference time-domain simulation that this mode is robust in crystal defects.