EVALUATION OF SEMICONDUCTOR OPTICAL-PARAMETERS FOR LASER-DIODES

The small-signal modulation and noise properties (electrical voltage, optical power and phase) of laser diodes depned on ten real parameters relating to the semiconductor material employed. Among these, the phase-amplitude coupling factor alpha is of particular importance. These parameters are evaluated for GaAs at 0.87-mu-m, GaInAsP at 1.55-mu-m and InAsSb at 3.87-mu-m at room temperature. Revised expressions for the optical gain are used. The light-hole contribution, the plasma effect and band-gap shrinkage are taken into account. The latter leads to a significant reduction of alpha, particularly below the peak-gain frequency. The alpha-factors for the three materials listed above are found to be, respectively, 2.9, 3.85 and 8.3 for conventional diodes.