Characterizing and Modeling Nonlinear Intermodulation Distortions in Modified Uni-Traveling Carrier Photodiodes

We present a physics-based model for nonlinear analysis of InGaAs/InP modified uni-traveling carrier (MUTC) photodiodes. At low frequencies (<;3 GHz), the Franz-Keldysh effect has been identified as the primary nonlinear mechanism in these MUTC photodiodes. The output third-order intercept point (OIP3) is used as a figure of merit for characterizing the nonlinear intermodulation distortion. The OIP3 behavior of the photodiode simulated using this model agrees well with measurements.