Abstract

External wavelength selective feedback to a multiple-longitudinal mode GaAlAs laser diode modifies the temporal behavior of laser wavelength and intensity as a function of time following a step current increase from that of a diode without feedback. For feedback of 20% and a current step of 110% of the threshold current, for the compound cavity, a single-laser diode mode is present within several tens of nanoseconds of the current onset. Following the current step the wavelength of the single dominant mode shifts about 3 Å to longer wavelengths in several microseconds, hops back to shorter wavelengths, and again shifts to longer wavelengths. The number of hops before the steady-state wavelength is reached depends on several cavity parameters. When a dc bias near the lasing threshold of the compound cavity is present and a current step of 10% of the threshold current is applied, the mode hops are absent.

© 1983 Optical Society of America