Interband quantum well cascade laser, with a blocking quantum well for improved quantum efficiency
US5799026A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 1, 1996 |
| Grant date | Aug 25, 1998 |
| Priority date | — |
| Expiry date | Nov 1, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/3419
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A gain region for an interban quantum well laser incudes (a) an emitter ron of semiconductor material having at least one conduction subband and at least one valence subband, these subbands being spaced apart by an energy band-gap; (b) a collector region of semiconductor material having at least one conduction subband and at least one valence subband, these subbands spaced apart by an energy band-gap; (c) a type-I or type-II active region; and (d) a blocking quantum well region of semiconductor material between the active region and the collector region, for keeping electrons in the active region from tunnelling or scattering into the collector region, but allowing electrons in the highest valence subband in the active region to pass into the collector region. Another aspect of the invention is a cascade laser made from a stack of these gain regions, connected in series, optical cladding regions at opposing ends of the stack, and a voltage source for applying a bias voltage to the stack, and an optical cavity perpendicular to the stacking axis fabricated by cleaving or other means.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.