Thermodynamic relation between optical gain and spontaneous emission in GaInP quantum well lasers

Summary form only given. In most calculations of optical gain it is assumed that, once captured into the well, carriers adopt quasi-equilibrium distributions specified by quasi Fermi levels, leading to a thermodynamic relationship between gain and emission spectra. This balance is used experimentally to transform measured emission spectra into optical gain, and in theoretical computations to obtain the spontaneous emission from the calculated optical gain. There is debate regarding the universality of this relationship, and apart from a comparison of 1.5 /spl mu/m laser structures there has been no wide-ranging test of this fundamental relation. We report comparisons of gain and emission spectra over a range of pumping levels and temperatures (20 K to 400 K) in GaInP/AlGaInP lasers.