Abstract

It has been demonstrated theoretically that a diode laser, when directly modulated at a rate comparable to its relaxation oscillation frequency, exhibits a period-doubling route to chaos¹. This prediction was based on a numerical solution of the deterministic noise-free rate equations that govern the interaction between electrons and photons in the laser. However, it is known that the output of a cw diode laser can exhibit large amplitude fluctuations with a frequency centered at the relaxation oscillation resonance². These fluctuations arise from the quantum nature of spontaneous emission and cannot be eliminated in real diode lasers. In effect, the laser acts as a noise-driven relaxation oscillator. In this paper we consider the effect of quantum noise on the predicted bifurcations to chaos of directly modulated diode lasers.

© 1985 Optical Society of America