Band Structure Engineering for Ultra-Low Threshold Laser Diodes
Abstract
While semiconductor lasers of high level of sophistication and reliability have been developed for present day fiberoptic telecommunications, demands for ultralow lasing threshold and ultrahigh modulation speed stem mainly from applications involving relatively short distance interconnections within a computer. The need for optics in computers arises from the increasing parallelism in modern computer architectures, which places heavy demands on input/output functions at gigahertz clock rates. Further considerations of using semiconductor lasers in computer optical interconnects shows that conventional semiconductor lasers are unacceptable for such purposes, the main problem being that they must be biased at or above lasing threshold for proper modulation behavior. This mode of operation requires a monitor photodiode and an active feedback circuit to stabilize the operating point. In a supercomputer where there are as many as a few hundred thousand interconnections, such feedback circuits will occupy a large amount of real estate and the bias current required will consume an unacceptable amount of power.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1988
- Accession Number
- ADA208629
Entities
People
- I. Ury
- Kam Y. Lau