Low-frequency mode-hopping optical noise in AlGaAs channeled substrate lasers induced by optical feedback

Experiments on mode-hopping noise induced by optical feedback are presented for AlGaAs CSP lasers. The influence of the amount of feedback and of the output power have been investigated. It turns out that the amount of excess noise associated with mode hopping strongly depends on the occurrence of hysteresis associated with the mode-hopping transition. The results indicate that the gain suppression near the lasing mode is asymmetric.