Direct-gap and indirect-gap transitions in strain-compensated Ge/SiGe multiple quantum wells with Ge-rich SiGe barriers have been studied by optical transmission spectroscopy and photoluminescence experiments. An sp3d5s∗ tight-binding model has been adopted to interpret the experimental results. Photoluminescence spectra and their comparison with theoretical calculations prove the existence of type-I band alignment in compressively strained Ge quantum wells grown on relaxed Ge-rich SiGe buffers. The high quality of the transmission spectra opens up other perspectives for application of these structures in near-infrared optical modulators.
|Autori:||Bonfanti M; Grilli E; Guzzi M; Virgilio M; Grosso G; Chrastina D; Isella G; von Kaenel H; Neels A|
|Titolo:||Optical transitions in Ge/SiGe multiple quantum wells with Ge-rich barriers|
|Anno del prodotto:||2008|
|Digital Object Identifier (DOI):||10.1103/PhysRevB.78.041407|
|Appare nelle tipologie:||1.1 Articolo in rivista|