A theoretical analysis of the transient intensity noise of semiconductor lasers

The nonstationary intensity noise of a high-speed modulated semiconductor laser is investigated. The analysis is based on a rate equation method with Langevin fluctuation sources. The variance and the autocorrelation function of the intensity noise are calculated analytically with a state-space approach. The time-variant statistical properties of the intensity noise are evaluated numerically for the turn-on transient. The numerical calculation indicates that the difference between intensity noise and photon number fluctuations during the turn-on transient can be neglected. It a shown that is significant part of the nonstationary intensity noise can be described as timing jitter of the relaxation oscillations.>