Influence of the α-factor in the output and noise of InGaAs fiber-grating laser

Theoretical investigations on the output power and intensity noise of fiber-grating semiconductor laser are performed based on intensive numerical integration of an improved time-delay rate equations of semiconductor laser over wide range of the α-factor and strong optical feedback. The simulation results indicated that the laser under strong optical feedback induce CW, pulsation or chaos operation depending on the value of α-factor and optical feedback strength. At higher values of α-factor and under very strong optical feedback the pulsing operation associated with reasonable intensity noise level (as low as quantum noise level) and becomes more dominant. We expect that fiber-grating laser subjected to strong optical feedback exhibits much more stability under higher values of α-factor which, means that the laser is locked at the external cavity frequency and pulsing operation is optimum for operating fiber-grating lasers.