Abstract

Fiber optic systems utilizing analog modulation have become an important area of use for semiconductor lasers, ranging from wideband microwave links for satellite communication that operate at multi-GHz frequencies, to CATV applications that operate at a few hundred megahertz. Semiconductor lasers under amplitude modulation experience certain nonlinearities that will degrade the performance of these analog transmission systems. These nonlinearities include harmonic distortion and intermodulation distortion. This paper reports the measured second harmonic, third harmonic, and intermodulation distortion of buried heterostructure lasers, and compares the measured results with those obtained by the perturbation analysis of laser rate equations. We have also evaluated the nonlinearities as a function of the laser structure. The laser structures measured include the capped-mesa and the etched-mesa distributed feedback lasers, multiple quantum well lasers, and Fabry-Perot lasers. We have compared the nonlinearities of these lasers operating at different output power levels and with various optical modulation index.

© 1989 Optical Society of America