A limitation on repetition rate of pulsations of junction lasers due to the repetitively Q-switched mechanism

The pulsing behavior of the double-section laser diode has been discussed using the nonlinear rate equation in a small-signal approximation and a trial-function approximation concentrating on the maximum repetition rate. It has been shown from the small-signal approximation that the double-section diode must exhibit an appropriate amplification coefficient to give rise to the sustained pulsations even if it has an amplifying and absorbing section and that the maximum repetition rate becomes very high for a particular amplification coefficient that decreases with increasing population inversion in the absorbing section. Nonlinear rate equations have been analyzed using the trial function approximation for the laser diode with an amplification coefficient expressed in a logarithmic function. The maximum repetition rate is approximately given in a simple form and is shown limited within a few gigahertz.