DocumentCode
1245521
Title
Effects of band nonparabolicity on the gain and current density in EuSe-PbSe0.78Te0.22-EuSe IV-VI semiconductor quantum-well lasers
Author
Khodr, Majed F. ; McCann, Patrick J. ; Mason, Bruce A.
Author_Institution
Sch. of Electr. Eng., Oklahoma Univ., Norman, OK, USA
Volume
32
Issue
2
fYear
1996
fDate
2/1/1996 12:00:00 AM
Firstpage
236
Lastpage
247
Abstract
In this work, a theoretical model that calculates the gain versus current density relationship for IV-VI semiconductor quantum-well lasers was developed. The model, based on Kane´s two-band model, solves for the anisotropy in the constant energy surfaces and for the strong nonparabolicity of the bands. The system investigated was the EuSe-PbSe 0.78Te0.22 quantum-well structure at 77 K. The nonparabolicity of the bands in the growth direction was found to shift the energy levels in the PbSe0.78Te0.22 quantum well to lower energies as compared to a quantum well with parabolic bands. Nonparabolicity of the bands also resulted in an energy dependent density of states in the junction plane of the structure. The effect of nonparabolicity in all directions on the gain versus current density relation is a reduction in the current density needed for any given gain and an increase in the gain saturation level. In addition to the 20% shift in the output lasing energy, nonparabolicity of the bands lowers the values of the confinement factor relative to those for the parabolic bands which in turn lowers the modal gain values
Keywords
II-VI semiconductors; band structure; current density; europium compounds; laser theory; lead compounds; quantum well lasers; semiconductor device models; 77 K; EuSe-PbSe0.78Te0.22; EuSe-PbSe0.78Te0.22-EuSe IV-VI semiconductor quantum-well laser gain; IV-VI semiconductor; Kane´s two-band model; PbSe0.78Te0.22; anisotropy; band nonparabolicity; confinement factor; constant energy surfaces; current density; current density relationship; energy dependent density of states; energy level shift; gain saturation level; growth direction; junction plane; modal gain values; nonparabolicity; output lasing energy; parabolic bands; strong nonparabolicity bands; theoretical model; Anisotropic magnetoresistance; Charge carrier processes; Current density; Effective mass; Ellipsoids; Energy states; Laser modes; Laser theory; Performance gain; Quantum well lasers; Semiconductor lasers; Tellurium;
fLanguage
English
Journal_Title
Quantum Electronics, IEEE Journal of
Publisher
ieee
ISSN
0018-9197
Type
jour
DOI
10.1109/3.481871
Filename
481871
Link To Document