Bit-error-rate saturation due to mode partition noise induced by optical feedback in 1.5micron single longitudinal mode C3 and DFB semiconductor lasers.

We report first measurements of the effect of optical feedback on the bit-error-rate (BER) as a function of received power of single longitudinal mode C3 and DFB semiconductor lasers. Mode-partition noise, induced by the optical feedback, can cause a bit-error-rate floor for large optical feedbacks but it is shown that high performance C3 lasers and especially DFB lasers can withstand very large optical feedbacks without system degradation.