Low frequency fluctuations in a semiconductor laser with phase conjugate feedback

We present numerical results obtained for a semiconductor laser with phase conjugate optical feedback. We observe both low and high frequency dynamics similar to that observed with conventional optical feedback. Here also the low frequency fluctuations correspond to power drop-outs while the high frequency fluctuations being associated with fast pulses in the power. Due to the absence of conventional external cavity modes in phase conjugate feedback, current models do not predict this behaviour.