-A A +A
Theoretical predictions indicate that the n-type Ge/Si− Ge multi-quantum-well system is the most promising material for the realization of a Si-compatible THz quantum cascade laser operating at room temperature. To advance in this direction, we study, both experimentally and theoretically, asymmetric coupled multi-quantum-well samples based on this material system, that can be considered as the basic building block of a cascade architecture. Extensive structural characterization shows the high material quality of strain-symmetrized structures grown by chemical vapor deposition, down to the ultrathin barrier limit. Moreover, THz absorption spectroscopy measurements supported by theoretical modeling unambiguously demonstrate inter-well coupling and wavefunction tunneling. The agreement between experimental data and simulations allows us to characterize the tunneling barrier parameters and, in turn …
American Physical Society
Publication date: 
2 Jan 2019

Chiara Ciano, Michele Virgilio, M Montanari, Luca Persichetti, Luciana Di Gaspare, Michele Ortolani, Leonetta Baldassarre, MH Zoellner, Oliver Skibitzki, Giacomo Scalari, Jérome Faist, Douglas J Paul, M Scuderi, Giuseppe Nicotra, Thomas Grange, Stefan Birner, Giovanni Capellini, Monica De Seta

Biblio References: 
Volume: 11 Issue: 1 Pages: 014003
Physical Review Applied