Optoelectronic feedback sustained pulsation of laser diodes at 1300 nm and 780 nm

In this paper, experimental results are reported on optoelectronic feedback sustained pulsation in multi-quantum well InGaAsP Laser diodes at 1300 nm and AlGaAs injection laser diodes at 780 nm. The feedback intensity plays an important role in feedback sustained pulsation in these two different kinds of laser diodes. When the feedback exceeds a certain level, the frequency of feedback sustained pulsation exhibits continuous, but staircase-like, dependence on the drive current with two characteristic slopes. The values of these slopes depend on the feedback level. Further, at appropriate feedback levels, there exists a bistability between the oscillation frequency and the drive current. The amplitude of feedback sustained pulsation can be modulated for subcarrier multiplexing applications. By further increasing the feedback level, period doubling phenomena was also observed in this dynamical system.