Berlin 2012 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

HL: Fachverband Halbleiterphysik

HL 43: Poster Session: Quantum Dots and Wires - Preparation and Characterization / Devices (incl. Laser) / Ultrafast Phenomena

HL 43.16: Poster

Tuesday, March 27, 2012, 09:30–12:30, Poster D

Low density 1.55 µm Indium phosphide based quantum dots — •Matusala Yacob, Mohamed Benyoucef, and Johann Peter Reithmaier — Institute of Nanostructure Technologies and Analytics (INA), Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, Germany

Due to their unique optical and mechanical properties, semiconductor quantum dots (QDs) can be used as a building block of quantum information processing. However, for this application circular and low density QDs operating in the telecom wavelength bands should be realized. In this work, we investigate the effect of growth parameters on shape, size and density of InAs QDs grown on lattice matched InAlGaAs/InP system using solid source molecular beam epitaxy. A red-shift of photoluminescence emission wavelength from 1.2 to 1.8 µm with increase in InAs coverage was observed. The QD density is reduced using two approaches. In the first approach, the substrate temperature was decreased after QD growth by introducing growth stop. This allows ripening of InAs structures creating large sized dots with relatively low density. In the second approach, the QD growth rate is decreased to increase the migration length of ad-atoms. Single dot emissions at 1.55 µm were observed confirming the formation of large sized dots with low QD density.