Small‐signal predictions of the well‐barrier hole burning model on quantum‐well laser dynamics

The mutual effect of well‐barrier (WB) hole burning and nonlinear gain on the resonance characteristics of quantum‐well lasers are investigated. A small‐signal impulse response is derived in order to connect the experimental fitting parameters (damping rate, resonance frequency, and K factor) with the parameters (capture time, ratio of carrier capture and release times, and nonlinear gain coefficient) of the WB model. This connection is examined from approximate analytic formulae, and limits on the 3 dB bandwidth are deduced from exact numerical data. It is shown that both mechanisms tend to increase the degree of damping, but the WB process becomes more efficient with nonlinear gain than without it.