Semiconductor laser
US5570386A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 1995 |
| Grant date | Oct 29, 1996 |
| Priority date | — |
| Expiry date | Jul 31, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/951
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The disclosed unipolar quantum cascade (QC) laser comprises a multiplicity of essentially identical active regions, with adjacent active regions separated by a superlattice carrier injection/relaxation region. A given active region contains a single quantum well with at least two electron states. Lasing is obtained without global intersubband population inversion. Instead, there is believed to exist local population inversion in a small region of k-space near k=0, corresponding to electron energies approximately within an optical phonon energy (.about.35 meV) from the bottom of the lower subband. A novel design feature that can be used to improve the thermal characteristics of substantially any QC laser is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.