Particle Swarm Optimization for Robust Nanobeam Photonic Crystal Cavities

During the summer of 2024 and following semester, I interned at the Quantum Photonics Group at the University of Maryland, College Park under Dr. Edo Waks. The lab faced issues with fabrication imperfections causing significant drops in the quality factor of photonic crystal cavities (how well light resonated within the cavity). To address this, my project explored using Particle Swarm Optimization (PSO) to optimize various parameters of the nanobeams using numerical simulations through the Finite-Difference Time-Domain (FDTD) method.

My methodology included adding an absorbing sidewall to the nanobeam in the FDTD simulations to mimic fabrication imperfections. This involved parameter sweeps to determine the optimal width and absorption coefficient of the sidewall to mimic the loss. Then, I conducted PSO optimization on the device, changing various parameters such as hole radius and spacing.

You can view the paper here and the poster here.