TY - JOUR
T1 - Direct bandgap quantum wells in hexagonal Silicon Germanium
AU - Peeters, Wouter H.J.
AU - van Lange, Victor T.
AU - Belabbes, Abderrezak
AU - van Hemert, Max C.
AU - Jansen, Marvin Marco
AU - Farina, Riccardo
AU - van Tilburg, Marvin A.J.
AU - Verheijen, Marcel A.
AU - Botti, Silvana
AU - Bechstedt, Friedhelm
AU - Haverkort, Jos E.M.
AU - Bakkers, Erik P.A.M.
PY - 2024/6/19
Y1 - 2024/6/19
N2 - Silicon is indisputably the most advanced material for scalable electronics, but it is a poor choice as a light source for photonic applications, due to its indirect band gap. The recently developed hexagonal Si1−xGex semiconductor features a direct bandgap at least for x > 0.65, and the realization of quantum heterostructures would unlock new opportunities for advanced optoelectronic devices based on the SiGe system. Here, we demonstrate the synthesis and characterization of direct bandgap quantum wells realized in the hexagonal Si1−xGex system. Photoluminescence experiments on hex-Ge/Si0.2Ge0.8 quantum wells demonstrate quantum confinement in the hex-Ge segment with type-I band alignment, showing light emission up to room temperature. Moreover, the tuning range of the quantum well emission energy can be extended using hexagonal Si1−xGex/Si1−yGey quantum wells with additional Si in the well. These experimental findings are supported with ab initio bandstructure calculations. A direct bandgap with type-I band alignment is pivotal for the development of novel low-dimensional light emitting devices based on hexagonal Si1−xGex alloys, which have been out of reach for this material system until now.
AB - Silicon is indisputably the most advanced material for scalable electronics, but it is a poor choice as a light source for photonic applications, due to its indirect band gap. The recently developed hexagonal Si1−xGex semiconductor features a direct bandgap at least for x > 0.65, and the realization of quantum heterostructures would unlock new opportunities for advanced optoelectronic devices based on the SiGe system. Here, we demonstrate the synthesis and characterization of direct bandgap quantum wells realized in the hexagonal Si1−xGex system. Photoluminescence experiments on hex-Ge/Si0.2Ge0.8 quantum wells demonstrate quantum confinement in the hex-Ge segment with type-I band alignment, showing light emission up to room temperature. Moreover, the tuning range of the quantum well emission energy can be extended using hexagonal Si1−xGex/Si1−yGey quantum wells with additional Si in the well. These experimental findings are supported with ab initio bandstructure calculations. A direct bandgap with type-I band alignment is pivotal for the development of novel low-dimensional light emitting devices based on hexagonal Si1−xGex alloys, which have been out of reach for this material system until now.
UR - http://www.scopus.com/inward/record.url?scp=85196375302&partnerID=8YFLogxK
U2 - 10.1038/s41467-024-49399-3
DO - 10.1038/s41467-024-49399-3
M3 - Article
C2 - 38898007
AN - SCOPUS:85196375302
SN - 2041-1723
VL - 15
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 5252
ER -