Dresden 2014 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 51: Quantum Wires: Optical Properties (organized by HL)
TT 51.7: Talk
Tuesday, April 1, 2014, 16:00–16:15, POT 112
Optical characterization and enhanced luminescence properties of InAs-InAsP core-shell nanowires — •Thomas Stettner1, Julian Treu1, Michael Bormann1, Hannes Schmeiduch1, Stefanie Morkötter1, Markus Döblinger2, Sonja Matich1, Peter Wiecha1, Kai Saller1, Benedikt Mayer1, Max Bichler1, Markus Christian Amann1, Jonathan Finley1, Gerhard Abstreiter1,3, and Gregor Koblmüller1 — 1Walter Schottky Institut and Physik Department, TU München, Garching, Germany — 2Department of Chemistry, Ludwig-Maximilians-Universität München, Munich, Germany — 3TUM Institute for Advanced Study, Garching, Germany
Using optical spectroscopy InAs nanowires (NW) grown by molecular beam epitaxy (MBE) and subsequently overgrown and passivated with an InAs1−xPx-shell by a hybrid metal-organic vapor phase epitaxy (MOVPE) process are studied in detail. With a microphotoluminescence (PL) setup designed for the mid infrared spectral range we demonstrate up to 100x enhancement of the InAs core signal [1]. By systematically varying both the shell thickness and the phosphorus content x(P) we show that it is possible to further tune the emission energy >100meV for comparatively low x(P) due to strain effects, which is confirmed by numerical simulation. For even higher P-content an asymmetric shell growth leads to a drastic reduction in PL efficiency/blueshift due to an onset of plastic relaxation which proves the importance to engineer a high quality InAs-InAsP core-shell interface for future use in photonic and optoelectronic devices like solar cells.
[1] J. Treu, et al., Nano Lett.2013, dx.doi.org/10.1021/nl403341x