Potential Limitations on Integrated Silicon Photonic Waveguides Operating in a Heavy Ion Environment

The impacts of heavy-ion induced radial ionization profiles in integrated silicon photonic waveguides are investigated. Drude theory is applied to the case of a highly excited silicon waveguide to obtain relations for relevant optical properties to the heavy ion induced electron-hole pair density. 3-D finite-difference time-domain simulations are used to ascertain transmission characteristics through a variety of ionization profiles. Transient free-carrier absorption and phase shifts due to transient free-carrier dispersion are identified as potential single event effect degradation mechanisms for photonic integrated circuits operated in space.