Two-dimensional imaging of III-V quantum dots confinement potential

¹  Solid States Physics, Electro-Optics Division, Soreq NRC - Yavne, 81800 Israel
²  School of Electrical Engineering-Physical Electronics, Faculty of Engineering, Tel-Aviv University Tel-Aviv, 69978, Israel
³  Departamento de Lenguajes y Sistemas Informáticos, CASEM, Universidad de Cádiz Pol. Rio San Pedro s/n. 11510, Puerto Real, Cadiz, Spain, EU
⁴  Applied Physics Department and the Center for Nano Science and Nanotechnology, The Hebrew University Jerusalem 91904, Israel

Corresponding author: paltiel@cc.huji.ac.il

Received: 13 September 2009
Accepted: 22 November 2009

Abstract

Composition, doping, size, and strain distribution within quantum dots, and at the dots-substrate interfaces, determine the confinement potential of electrons and holes creating a complex band structure. We use ultra-high vacuum Kelvin probe force microscopy to obtain the two-dimensional confinement potential in and around InAs and InSb dots epitaxially grown on GaAs. It is found that the potential manifests rich features governed by the strain and composition variations in the vicinity of the individual quantum dots. The results can adjust or confirm theoretical predictions for many epitaxial dots systems.