Modulation Crosstalk and Reduction in Distributed Feedback Laser Diode and Monitor Photodiode Monolithically Integrated Optical Transceivers

In this paper, modulation crosstalk from 1310 nm upstream optical signals to 1490 nm downstream optical signals in an distributed feedback laser diode and monitor photodiode (DFB-LD and MPD) monolithically integrated optical transceiver has been studied numerically through the time-domain traveling wave (TDTW) model. Interaction between the $1310/1490$ nm wavelengths throughout the cavity originated from both cross gain modulation and cross phase modulation are the physical source of the crosstalk in the device, which were analyzed numerically in detail in the paper. A new structure is proposed to reduce the modulation crosstalk resulted from the interaction. Simulation shows that the modulation crosstalk can be drastically reduced by applying an adjustable current on the phase tuning section inserted between the DFB-LD and MPD, which verifies our design. Polarization and temperature dependence on the modulation crosstalk are also discussed.