Photoluminescence study of as-grown self-catalyzed GaAs/AlGaAs core-shell nanowires
A macro-photoluminescence study of self-catalyzed nanowires, using a specialized
setup for this purpose, has been performed. Several samples were even compared
to single nanowire micro-photoluminescence measurements, on the same
samples, done by other students in the nanowire group at NTNU. The macrophotoluminescence measurements were done by changing parameters such as temperature and excitation power. A 532 nm laser was used to excite the wires and the
photoluminescence was measured by a CCD detector attached to a spectroscope.
Using macro-photoluminescence measurements in a qualitative comparison with
measurements done on single nanowires by micro-photoluminescence spectroscopy
can give the researcher a decent understanding of the quality of the sample and its
contributions to photoluminescence. Measurements done in this thesis show probable
contributions from most types of transitions expected in zinc-blende nanowires,
consisting of such defects as dense zinc-blende/wurtzite heterostructures, highly
twinned regions, but also from nanowires of higher purity.
As nanowires move closer to the realization of e.g. nanowire based solar cells,
such macro-photoluminescence measurements will become increasingly important
in deciding the overall quality of the grown structures.
Place, publisher, year, edition, pages
Institutt for elektronikk og telekommunikasjon , 2012. , 81 p.
ntnudaim:8008, MTEL elektronikk, Nanoelektronikk og mikrosystemer
IdentifiersURN: urn:nbn:no:ntnu:diva-18921Local ID: ntnudaim:8008OAI: oai:DiVA.org:ntnu-18921DiVA: diva2:566373
Weman, Helge, ProfessorOlk, Phillip