OPTIMIZED DESIGN PARAMETERS OF INGAAS-INP QUANTUM-WELL LASERS

Citation
P. Vaya et al., OPTIMIZED DESIGN PARAMETERS OF INGAAS-INP QUANTUM-WELL LASERS, Materials science & engineering. B, Solid-state materials for advanced technology, 35(1-3), 1995, pp. 17-23
Citations number
13
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Material Science","Physics, Condensed Matter
ISSN journal
0921-5107
Volume
35
Issue
1-3
Year of publication
1995
Pages
17 - 23
Database
ISI
SICI code
0921-5107(1995)35:1-3<17:ODPOIQ>2.0.ZU;2-C
Abstract
A complete theoretical analysis is carried out for the design of a lat tice matched InGaAs-InP quantum well (QW) laser taking into account ca rrier collection, intraband relaxation and employing dipole moment mat rix elements for gain calculations. The effects of temperature, carrie r concentration, and well width on the linear gain are studied. The ma ximum gain vs. current density curves are obtained for multiple temper atures and well width conditions. It is seen that for operation with c arrier concentration above 2 x 10(-18) cm(-3), maximum gain decreases with increase in well width. A significant reduction in gain is observ ed as the temperature increases. The gain spectra for In0.53Ga0.47As-I nP QW structure for TE modes, display a gradual increase at the transi tion energy when broadening due to intraband relaxation is taken into account. However, with broadening, gain peaks are not fixed at the wav elengths determined by transitions between the quantized levels but ar e seen to be shifted towards shorter wavelengths for finite values of intraband relaxation time. For a given facet reflectivity, well width laser losses and length of the laser, a single quantum well may not gi ve the lowest current to achieve lasing. By increasing the number of w ells, the threshold current can be decreased. The approach for optimis ing the QW to achieve the lowest threshold is presented. Similarly, fo r a given facet reflectivity, well width, laser losses and the number of quantum wells, the length of the cavity can also be optimized to re duce the threshold current.