Impurity-doped semiconductor laser device for single wavelength oscillation
US4928285A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 23, 1989 |
| Grant date | May 22, 1990 |
| Priority date | — |
| Expiry date | Feb 23, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/32391
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An impurity-doped double-heterostructure semiconductor laser adapted for single-longitudinal-mode operation is disclosed which includes a semiconductive substrate and a mesa of double-heterostructure formed over the substrate. The mesa comprises an active layer serving as a light-emitting layer, a waveguiding layer adjacent to the active layer and clad layers interposing the active layer and the waveguiding layer therebetween. A high-resistively layer is formed to bury the lateral surfaces of the mesa. The active layer contains impurities of a rare earth element with a previously selected concentration. The limited concentration of impurities is high enough to confine only light components falling within a specific range of wavelength, of all the light components produced in the active layer when the laser device is operative, within the active layer so as to provide single wavelength laser oscillation and low enough to inhibit the initiation of spontaneous emission of the rare earth element within the active layer. For example, the concentration may be set to 1.times.10.sup.18 cm.sup.-3 or below.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.