Terahertz absorption-saturation and emission from electron-doped germanium quantum wells
Terahertz absorption-saturation and emission from electron-doped germanium quantum wells
Ciano, C.; Virgilio, M.; Bagolini, L.; Baldassarre, L.; Pashkin, O.; Helm, M.; Montanari, M.; Persichetti, L.; Di Gaspare, L.; Capellini, G.; Paul, D. J.; Scalari, G.; Faist, J.; de Seta, M.; Ortolani, M.
Abstract
We study radiative relaxation at terahertz frequencies in n-type Ge/SiGe quantum wells, optically pumped with a terahertz free electron laser. Two wells coupled through a tunneling barrier are designed to operate as a three-level laser system with non-equilibrium population generated by optical pumping around the 1→3 intersubband transition at 10 THz. The non-equilibrium subband population dynamics are studied by absorption-saturation measurements and compared to a numerical model. In the emission spectroscopy experiment, we observed a photoluminescence peak at 4 THz, which can be attributed to the 3→2 intersubband transition with possible contribution from the 2→1 intersubband transition. These results represent a step towards silicon-based integrated terahertz emitters.
Beteiligte Forschungsanlagen
- Strahlungsquelle ELBE DOI: 10.17815/jlsrf-2-58
Verknüpfte Publikationen
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 30769) publication
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Optics Express 28(2020), 7245-7258
DOI: 10.1364/OE.381471
Cited 12 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-30769