Abstract

Bistable semiconductor lasers have potential applications in future optical communication, optical switching, optical computing, and so on [1] Although gain saturation alone could account for the bistability, the inclusion of absorption saturation could make the bistability easier to occur [2]. As a result, multi-electrode semiconductor lasers are usually used for optical bistability. In this work, we report that bistability exists in the semiconductor lasers without multiple sections. Using multiple quantum wells of different widths, both gain quenching and saturable absorption could occur in the same region for bistability The semiconductor lasers that exhibit optical bistability have four quantum wells with their widths 20Å, 33Å, 56Å, and 125Å, respectively, separated by 150 Å Al₀₂Ga₀₈As barrier. An external-cavity configuration with broadband tunability was used for the bistability experiment. Different behaviors of bistability had been discovered for different wavelengths. Fig 1 shows an L-I curve with obvious bistability. The details of experiments will be discussed in the presentation.

© 2000 IEEE