A Microscopic Approach To Amplitude Modulation With Small Signal Of Current

A microscopic approach to semiconductor injection laser dynamics is discussed to investigate the amplitude modulation with a small current signal in semiconductor lasers. An expression for the resonance frequency υ r is obtained as a function of microscopic parameters which characterize the laser system. This expression can be compared with the one derived from a standard rate equations approach, showing the existence of an additional factor. This factor leads to the prediction of a larger resonance frequency and consequently to a better agreement with the experimental data. We investigate the problem of amplitude modulation with small current signal in semiconductor lasers deriving an expression for the resonance frequency as a function of microscopic parameters which characterize the laser system and as a function of the injected current. This approach is based on the analysis of the competition among the fundamental microscopic processes typical of light-matter interaction and of the loss and pumping mechanisms that are at work in a laser system. The starting point of the SLTMB model for the analysis of semiconductor laser modulation by a small signal of current is the couple of equations describing the temporal evolution of the two variables A 2 (intensity of the coherent field in the optical cavity) and D (the carrier population inversion ).