Loading...
Please wait, while we are loading the content...
Similar Documents
Long lifetimes of quantum-dot intersublevel transitions in the terahertz range.
| Content Provider | Semantic Scholar |
|---|---|
| Author | Zibik, Evgeny A. Grange, T. Carpenter, Ben A. Porter, Natalia Ferreira, Robson De Jesus Bastard, G'erald Stehr, Dominik Winnerl, Stephan Helm, Manfred Liu, Huiyan Y. Skolnick, M. S. Wilson, Luke R. |
| Copyright Year | 2009 |
| Abstract | Carrier relaxation is a key issue in determining the efficiency of semiconductor optoelectronic device operation. Devices incorporating semiconductor quantum dots have the potential to overcome many of the limitations of quantum-well-based devices because of the predicted long quantum-dot excited-state lifetimes. For example, the population inversion required for terahertz laser operation in quantum-well-based devices (quantum-cascade lasers) is fundamentally limited by efficient scattering between the laser levels, which form a continuum in the plane of the quantum well. In this context, semiconductor quantum dots are a highly attractive alternative for terahertz devices, because of their intrinsic discrete energy levels. Here, we present the first measurements, and theoretical description, of the intersublevel carrier relaxation in quantum dots for transition energies in the few terahertz range. Long intradot relaxation times (1.5 ns) are found for level separations of 14 meV (3.4 THz), decreasing very strongly to approximately 2 ps at 30 meV (7 THz), in very good agreement with our microscopic theory of the carrier relaxation process. Our studies pave the way for quantum-dot terahertz device development, providing the fundamental knowledge of carrier relaxation times required for optimum device design. |
| Starting Page | 265 |
| Ending Page | 274 |
| Page Count | 10 |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://www.hzdr.de/FWI/Jahresbericht/2009/Zibik.pdf |
| PubMed reference number | 19684587v1 |
| Alternate Webpage(s) | https://doi.org/10.1038/nmat2511 |
| DOI | 10.1038/nmat2511 |
| Journal | Nature materials |
| Volume Number | 8 |
| Issue Number | 10 |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Cascade Device Component Devices Energy, Physics Iodine I 124-cRGDY-PEG-C Dots Lasers Quantum Dots Semiconductors Terahertz |
| Content Type | Text |
| Resource Type | Article |
