Two-Photon Absorption based Silicon Photodetector with Topology Optimized cavity

A topologically optimized photonic cavity with an integrated lateral p-i-n structure-based silicon(Si) photodetector has been fabricated. The silicon based cavity allows for the integration of photodetectors (PDs) in CMOS technology, bypassing challenges associated with adding other materials. The goal of the topological optimization is to maximize the rate of two-photon absorption in silicon, while maintaining small dimensions. The fabricated device was characterized, obtaining a resonant wavelength at 1543 nm with a Q-factor of 6315 and a responsivity of 0.21 mA/W while maintaining a low dark current.