title: Quantum dots in InAs nanowires induced by surface potential fluctuations.
abstract: Back-gated InAs nanowire field-effect transistors are studied focusing on the formation of intrinsic quantum dots, i.e. dots not intentionally defined by electrodes. Such dots have been studied before, but the suggested explanations for their origin leave some open questions, which are addressed here. Stability diagrams of samples with different doping levels are recorded at electron temperatures below 200 mK, allowing us to estimate the number and size of the dots as well as the type of connection, i.e. in series or in parallel. We discuss several potential physical origins of the dots and conclude that they are most probably induced by potential fluctuations at the nanowire surface. Additionally, we show that via gate voltage and doping, the samples can be tuned to different regimes of Coulomb blockade.
authors.affiliation: Peter Grünberg Institute (PGI-9), Forschungszentrum Jülich, 52425 Jülich, Germany. Jülich Aachen Research Alliance, Fundamentals of Future Information Technology (JARA-FIT), Germany.
authors.forename: Karl
authors.initials: K
authors.lastname: Weis
authors.forename: Stephan
authors.initials: S
authors.lastname: Wirths
authors.forename: Andreas
authors.initials: A
authors.lastname: Winden
authors.forename: Kamil
authors.initials: K
authors.lastname: Sladek
authors.forename: Hilde
authors.initials: H
authors.lastname: Hardtdegen
authors.forename: Hans
authors.initials: H
authors.lastname: Lüth
authors.forename: Detlev
authors.initials: D
authors.lastname: Grützmacher
authors.forename: Thomas
authors.initials: T
authors.lastname: Schäpers