Evidence for large monomolecular recombination contribution to threshold current in 1.3 μm GaInNAs semiconductor lasers

The spontaneous emission, L. through a window in the substrate electrode of 1.3 mum GaInNAs MQW lasers was studied as a function of current. I, and temperature, T. Close to room temperature, a characteristic temperature at threshold T-o(L) similar or equal to T was observed as expected for band-to-band recombination in ideal quantum well devices. However, T-o(I-th) similar or equal to T/3 indicating other processes occur. Analysis of the variation of L with I, reveals that monomolecular recombination contributes more than 50% to the total current at threshold and also that some Auger recombination may be present.