Transmissions of photonic topological modes through channels with different shapes

We study the transmission behavior of photonic topological mode through topological microwave channels with different shapes in a two-dimensional photonic crystal platform by the COMSOL Multiphysics software. A four-source-array is set to excite the topological modes. We find that topological modes with up and down pseudospin both can be excited in one channel although they have different intensity. Different channel can provide different transmission ratio between two opposite directions (rightward and leftward). These results suggest the topological mode might undergo a spin-flip process at the exit end face or the sharp bending position of the topological channel.

Automated summary

Through studying the transmission behavior of photonic topological modes through different shapes of topological microwave channels, we found that topological modes with different intensity of up and down pseudospin can be excited in one channel, providing different transmission ratios between opposite directions. These results suggest a spin-flip process may occur at the exit end face or sharp bending position of the topological channel.