Abstract
A theoretical study has been made to compare the quantum efficiencies of interwell and intrawell radiative transitions in quantum cascade lasers based on Al𝑥Ga1−xAs/GaAs technology. Radiative and nonradiative intersubband transition rates were calculated for a range of temperatures between 1 and 300 k at an applied electric field of of 4 kV cm−1 for structures designed to emit in both mid-infrared and far-infrared frequency ranges. It is found that the internal quantum efficiency of mid-infrared devices is a maximum for diagonal, or interwell, transitions. Conversely, for the far-infrared devices, the quantum efficiency is a maximum for vertical, or intrawell, transitions.
| Original language | English |
|---|---|
| Pages (from-to) | 1999-2001 |
| Number of pages | 3 |
| Journal | Applied Physics Letters |
| Volume | 75 |
| Issue number | 14 |
| Early online date | 30 Sep 1999 |
| DOIs | |
| Publication status | Published - 4 Oct 1999 |
| Externally published | Yes |