External optical feedback resistant characteristics in partially-corrugated-waveguide laser diodes

In subcarrier multiplexing (SCM) systems low relative intensity noise (RIN) is essential to realize high carrier-to-noise ratio. However, external optical feedback from the surfaces of other devices, such as the optical connectors used in fiber communication systems, induces operational instability in laser diodes and increases RIN. Partially-corrugated-waveguide laser diodes (PC-LDs) show attractive low intermodulation distortion characteristics due to their uniform electric field. In this paper, external optical feedback resistant characteristics in PC-LDs were analyzed based on the mode-competition theory.