Open AccessDirect-bandgap luminescence at room-temperature from highly-strained Germanium nanocrystals
Author(s) -
Latha Nataraj,
Fujun Xu,
Sylvain G. Cloutier
Publication year - 2010
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.18.007085
Subject(s) - materials science , germanium , luminescence , photoluminescence , optoelectronics , raman spectroscopy , direct and indirect band gaps , spectroscopy , microelectronics , band gap , nanocrystal , photonics , silicon , optics , nanotechnology , physics , quantum mechanics
Efficient room-temperature luminescence at optical telecommunication wavelengths and originating from direct band-to-band recombination has been observed in tensile-strained germanium nanocrystals synthesized by mechanical grinding techniques. Selected area electron diffraction, micro-Raman and optical-absorption spectroscopy measurements indicate high tensile-strains while combined photoluminescence spectroscopy, excitation-power evolution and time-resolved measurements suggest direct band-to-band recombination. Such band-engineered germanium nanocrystals offer great possibilities for silicon-photonics integration due to their superb light-emission properties, facile fabrication and compatibility with standard microelectronic processes.