Influence of cavity-trapped amplified luminescence on laser diode optical properties

The values of power densities for the amplified luminescence (superluminescence) trapped in laser diode (LD) cavity and averaged by LD spectrum have been calculated as a function of the current and temperature for different types of LDs. The (Al,Ga)As, InGaAs/(Al,Ga)As and InGaAsP/InP heterostructures with the bulk and quantum well active layers have been analyzed. In the case of powerful and surface-emitting LDs the amplified luminescence was demonstrated to have considerable influence (comparable in some instances with nonradiative Auger recombination) on the threshold current, maximum output power and temperature dependence of optical gain spectra. Using Mathematica computer program the effect of the amplified luminescence on the laser transient processes has been studied by numerical solving the LD rate equations. The study made it apparent that the LD cavity-trapped amplified luminescence change laser delay time, peak intensity, pulse duration and can be in a position to limit seriously the maximum modulation frequency of high speed LDs. Results obtained here should be taken into account for analysis of injection lasers operated in high-bit-rate information systems.