title: Lasing from Glassy Ge Quantum Dots in Crystalline Si.
abstract: Semiconductor light-emitters compatible with standard Si integration technology (SIT) are of particular interest for overcoming limitations in the operating speed of microelectronic devices. Light sources based on group IV elements would be SIT-compatible, but suffer from the poor optoelectronic properties of bulk Si and Ge. Here we demonstrate that epitaxially grown Ge quantum dots (QDs) in a defect-free Si matrix show extraordinary optical properties if partially amorphized by Ge-ion bombardment (GIB). In contrast to conventional SiGe nanostructures, these QDs exhibit dramatically shortened carrier lifetimes and negligible thermal quenching of the photoluminescence (PL) up to room temperature. Microdisk resonators with embedded GIB-QDs exhibit threshold behavior as well as a superlinear increase of the integrated PL intensity with concomitant line width narrowing as the pump power increases. These findings demonstrate light amplification by stimulated emission in a fully SIT-compatible group IV nanosystem.
authors.affiliation: Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz , Altenbergerstrasse 69, A-4040 Linz, Austria.
authors.forename: Martyna
authors.initials: M
authors.lastname: Grydlik
authors.affiliation: Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz , Altenbergerstrasse 69, A-4040 Linz, Austria.
authors.forename: Florian
authors.initials: F
authors.lastname: Hackl
authors.affiliation: Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz , Altenbergerstrasse 69, A-4040 Linz, Austria.
authors.forename: Heiko
authors.initials: H
authors.lastname: Groiss
authors.affiliation: Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz , Altenbergerstrasse 69, A-4040 Linz, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Glaser
authors.affiliation: Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz , Altenbergerstrasse 69, A-4040 Linz, Austria.
authors.forename: Alma
authors.initials: A
authors.lastname: Halilovic
authors.affiliation: Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz , Altenbergerstrasse 69, A-4040 Linz, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Fromherz
authors.affiliation: Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz , Altenbergerstrasse 69, A-4040 Linz, Austria.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Jantsch
authors.affiliation: Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz , Altenbergerstrasse 69, A-4040 Linz, Austria.
authors.forename: Friedrich
authors.initials: F
authors.lastname: Schäffler
authors.affiliation: Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz , Altenbergerstrasse 69, A-4040 Linz, Austria.
authors.forename: Moritz
authors.initials: M
authors.lastname: Brehm
keywords: laser; microdisks; photoluminescence; quantum dots; silicon photonics