EFFECTIVE BLOCH EQUATIONS FOR SEMICONDUCTOR-LASERS AND AMPLIFIERS

A set of effective Bloch equations is established for semiconductor bu lk or quantum-well media, The model includes the nonlinear carrier-den sity dependence of the gain and refractive index and their respective dispersions (frequency dependences), A comparative study is performed between the full microscopic semiconductor Bloch equations and this ef fective model for pulse propagation to show the range of validity of t he present model. The results show that this model agrees well with th e microscopic model provided carrier depletion is the dominant saturat ion mechanism relative to the plasma heating, The effective Bloch equa tions provide an accurate and practical model for modeling amplifiers with pulses of duration, greater than a few picoseconds, By capturing the large bandwidth and the carrier density dependence of the gain, it also provides a reliable model for studying the complex spatiotempora l multilongitudinal and transverse mode dynamics of a variety of wide- aperture high-power semiconductor lasers, The model goes beyond the tr aditional rate equations and is computationally much more efficient to simulate than the full model.