High internal differential efficiency mid-infrared quantum cascade lasers
| Autor: | Jae Cheol Shin, Luke J. Mawst, Dan Botez, Thomas Earles, Jeremy Kirch, Gun-Kim Doo, D. Lindberg, K. Oresick, C. Boyle, Chun Chieh Chang, Minhyeok Jo, Honghyuk Kim, C. Sigler |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
010302 applied physics
Temperature sensitivity Materials science Wavelength range business.industry Mid infrared 02 engineering and technology 021001 nanoscience & nanotechnology Laser 01 natural sciences law.invention law Cascade 0103 physical sciences Optoelectronics 0210 nano-technology Quantum cascade laser business Quantum |
| Zdroj: | SPIE Proceedings. |
| ISSN: | 0277-786X |
| Popis: | Implementation of the step-taper active-region (STA) design to 8-9 μm-emitting quantum cascade lasers (QCLs) has resulted in both high T0 and T1 values: 220 K and 665 K, and short lower-level lifetimes: 0.12 ps. In turn, the internal differential efficiency ηid, which is the product of the injection efficiency and the differential laser-transition efficiency, reaches values as high as 86 % for both 8.4 μm- and 8.8 μm-emitting QCLs. Such ηid values are 30-50% higher than those obtained from conventional QCLs emitting in the 7-11 μm wavelength range. Achieving both carrier-leakage suppression and miniband-like carrier extraction in mid-infrared (IR) QCLs leads to ηid values close to the fundamental limit of ~ 90 %. In turn, the currently employed fundamental wallplug-efficiency limits over the mid-IR wavelength range have to be increased by ~ 34 % (e.g., the wallplug-efficiency limit at λ= 4.6 μm increases from 29 % to 39 %). Preliminary results from STA-type 4.8-5.0 μm-emitting QCLs include 1.5 W CW operation, and 77 % internal differential efficiency; that is, 30-50% higher than the ηid values obtained from conventional 4.0-6.5μm-emitting QCLs. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|