Optical properties of Cd(Zn)Se/ZnMgSSe heterostructures with fractional QD-like CdSe insertions at high excitation levels

It was found that in the Cd(Zn)Se/ZnMgSSe heterostructures with QD-like CdSe insertions in the lasing regime the structure changes take place manifesting itself, first, in the irreversible blue shift of the laser radiation spectra. This process depends on excitation intensity and on the cavity length, correlating with the inherent radiation density in the cavity. At excitation densities above 250 kW/cm², the reduction of the radiative efficiency was observed. The second process is the increase of radiation intensity during laser operation under certain excitation conditions caused by the self-annealing of the laser structure induced by the inherent laser light and resulting in a decrease of the laser threshold by about 15-20%. Choosing the appropriate excitation regime, one may prolong the lifetime of this type of lasers.