Long exciton lifetimes in stacking-fault-free wurtzite GaAs nanowires

Journal Article · Mon Dec 01 04:00:00 EST 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4903482· OSTI ID:22402408

Furthmeier, Stephan; Dirnberger, Florian; Hubmann, Joachim; Bauer, Benedikt; Korn, Tobias; Schüller, Christian; Zweck, Josef; Reiger, Elisabeth; Bougeard, Dominique ^[1]

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1. Institut für Experimentelle und Angewandte Physik, Universität Regensburg, D-93040 Regensburg (Germany)

We present a combined photoluminescence and transmission electron microscopy study of single GaAs nanowires. Each wire was characterized both in microscopy and spectroscopy, allowing a direct correlation of the optical and the structural properties. By tuning the growth parameters, the nanowire crystal structure is optimized from a highly mixed zincblende–wurtzite structure to pure wurtzite. We find the latter one to be stacking-fault-free over nanowire lengths up to 4.1 μm. We observe the emission of purely wurtzite nanowires to occur only with polarization directions perpendicular to the wurtzite c{sup ^}-axis, as expected from the hexagonal unit cell symmetry. The free exciton recombination energy in the wurtzite structure is 1.518 eV at 5 K with a narrow linewidth of 4 meV. Most notably, these pure wurtzite nanowires display long carrier recombination lifetimes of up to 11.2 ns, exceeding reported lifetimes in bulk GaAs and state-of-the-art 2D GaAs/AlGaAs heterostructures.

• OSTI ID: 22402408
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 22 Vol. 105; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM ARSENIDES
CARRIER LIFETIME
CHARGE CARRIERS
GALLIUM ARSENIDES
NANOWIRES
PHOTOLUMINESCENCE
RECOMBINATION
SPECTROSCOPY
STACKING FAULTS
TRANSMISSION ELECTRON MICROSCOPY
ZINC SULFIDES