Abstract
The feasibility and fundamental difficulty in developing the infrared intersubband quantum cascade lasers in shorter wavelength range were discussed theoretically. The band offsets of InAs/AlSb on GaSb substrate, InAs/Al0.6Ga0.4Sb on GaSb substrate, and In0.53Ga0.47As/In0.52Al0.48As on InP substrate, and the confined states of their quantum wells with and without an applied electric field were analyzed and calculated by using the fundamental assumption of model-solid theory, strained band structure theory, empirical-two-band model for non-parabolic band, and methods of propagation matrix and laminar approach. It was found that the greatest energy difference between subband edges can not exceed 56-62% of the conduction band offset, and will be decreased further by the indirect valley. A designed structure of intersubband quantum cascade laser consisting of 250 coupled quantum wells in 25 periods under electric field 100 kV/cm for emitting the shortest wavelength 2.88 μm was proposed.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1-6 |
| Number of pages | 6 |
| Journal | Hongwai Yu Haomibo Xuebao/Journal of Infrared and Millimeter Waves |
| Volume | 20 |
| Issue number | 1 |
| State | Published - Feb 1 2001 |
| Externally published | Yes |
Keywords
- Band offset
- Intersubband transition
- Nonparabolic band
- Quantum cascade laser
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics