Regensburg 2022 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

HL: Fachverband Halbleiterphysik

HL 25: Poster 1

HL 25.72: Poster

Mittwoch, 7. September 2022, 18:00–20:00, P2

Density Modulation of InAs/GaAs Quantum Dots and Pre Dots — •Peter Zajac¹, Nikolai Bart¹, Christian Dangel², Kai Müller³, Andreas D. Wieck¹, Jonathan Finley², and Arne Ludwig¹ — ¹Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, Germany — ²Walter Schottky Institut and Physik Department, Technische Universität München, Am Coulombwall 4, 85748 Garching, Germany — ³Walter Schottky Institut and Department of Electrical and Computer Engineering, Technische Universität München, Am Coulombwall 4, 85748 Garching, Germany

Epitaxial layer-by-layer growth without rotation of the substrate creates a thickness gradient along the surface with alternating smooth and rough layer areas. InAs quantum dots (QDs) grown on top of a GaAs gradient layer exhibit a density modulation along this gradient, which is studied with macro photoluminescence spectroscopy and atomic force microscopy (AFM). The periodicity of the modulation can be varied from a few hundred microns to several millimeters, depending on the thickness of the underlying gradient layer. Automated AFM measurements, covering multiple modulation periods along the gradient allow the investigation of wetting layer roughness, QD density and density of a smaller species of QDs, termed pre dots. AFM data analysis and extraction of parameters such as QD and monolayer step density is presented.

Bart, N., Dangel, C. et al. Wafer-scale epitaxial modulation of quantum dot density. Nat Commun 13, 1633 (2022).