Topology Optimization of Low-Loss Z-Bend 2D Photonic Crystal Waveguide

In this article, we design a low-loss, high-bandwidth Z-bend photonic silicon crystal waveguide bending in a triangular lattice through topology optimization. Based on the topological optimization method, we change the relative position of air holes in the global scope to maximize the transmittance and bandwidth of the waveguide. The simulation results indicate that the transmission characteristics can be effectively improved with our method. After the optimization, the loss of the waveguide can be reduced to -5 dB and the bandwidth can increase to 160 nm. Our research has great significance for further optimizing the propagation of light in photonic crystals.