Interband Coherence and Inversionless Bistability in Semiconductor Lasers

✍ Scribed by Guo Qin Ge; P.T. Leung

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 64 KB
• Volume: 221
• Category: Article
• ISSN: 0370-1972
• DOI: 10.1002/1521-3951(200009)221:1<403::aid-pssb403>3.0.co;2-9

✦ Synopsis

We study how interband coherence can be set up by an injection current and a coherent pumpfield. In the absence of the pump-field, the injection current is the only source to establish the interband coherence in a semiconductor laser system. It shows that a strongly coupled high-Q microcavity has a low lasing threshold value, which corresponds to the threshold intensity being unity. When an external pump-field serving as another mechanism to create the interband coherence is applied, the threshold value of the injection current can be lowered and it vanishes for sufficiently strong field. When the pump-field exceeds a threshold value, it is possible to achieve a bistability in the inversionless region.