Controlling the error mechanism in a tunable-barrier nonadiabatic charge pump by dynamic gate compensation

authored by: Frank Hohls, Vyacheslavs Kashcheyevs, Friederike Stein, Tobias Wenz, Bernd Kaestner, Hans W. Schumacher
Abstract: Single-electron pumps based on tunable-barrier quantum dots are the most promising candidates for a direct realization of the unit ampere in the recently revised International System of Units (SI): they are simple to operate and show high precision at high operation frequencies. The current understanding of the residual transfer errors at low temperature is based on the evaluation of back-tunneling effects in the decay cascade model. This model predicts a strong dependence on the ratio of the time-dependent changes in the quantum dot energy and the tunneling barrier transparency. Here we employ a two-gate operation scheme to verify this prediction and demonstrate control of the back-tunneling error. We derive and experimentally verify a quantitative prediction for the error suppression, thereby confirming the basic assumptions of the back-tunneling (decay cascade) model. Furthermore, we demonstrate a controlled transition from the back-tunneling dominated regime into the thermal (sudden decoupling) error regime. The suppression of transfer errors by several orders of magnitude at zero magnetic field was additionally verified by a sub-ppm precision measurement.
External Organisation(s): National Metrology Institute of Germany (PTB)
University of Latvia
Type: Article
Journal: Physical Review B
Volume: 105
ISSN: 2469-9950
Publication date: 20.05.2022
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Electronic, Optical and Magnetic Materials, Condensed Matter Physics
Electronic version(s): https://doi.org/10.1103/PhysRevB.105.205425 (Access: Open)

BibTeX

@article{0fd69274848d4704ba28765c91f63ae4,
title = "Controlling the error mechanism in a tunable-barrier nonadiabatic charge pump by dynamic gate compensation",
abstract = "Single-electron pumps based on tunable-barrier quantum dots are the most promising candidates for a direct realization of the unit ampere in the recently revised International System of Units (SI): they are simple to operate and show high precision at high operation frequencies. The current understanding of the residual transfer errors at low temperature is based on the evaluation of back-tunneling effects in the decay cascade model. This model predicts a strong dependence on the ratio of the time-dependent changes in the quantum dot energy and the tunneling barrier transparency. Here we employ a two-gate operation scheme to verify this prediction and demonstrate control of the back-tunneling error. We derive and experimentally verify a quantitative prediction for the error suppression, thereby confirming the basic assumptions of the back-tunneling (decay cascade) model. Furthermore, we demonstrate a controlled transition from the back-tunneling dominated regime into the thermal (sudden decoupling) error regime. The suppression of transfer errors by several orders of magnitude at zero magnetic field was additionally verified by a sub-ppm precision measurement.",
author = "Frank Hohls and Vyacheslavs Kashcheyevs and Friederike Stein and Tobias Wenz and Bernd Kaestner and Schumacher, {Hans W.}",
note = "Funding information: We thank Christoph Leicht and Thomas Weimann for help with the sample fabrication, Holger Marx and Klaus Pierz for providing the GaAs/AlGaAs heterostructure, Martin G{\"o}tz for the calibration of the ULCAs, and Thomas Gerster for critical reading of the paper. This paper was supported in part by the Joint Research Projects e-SI-Amp (Project No. 15SIB08) and SEQUOIA (Project No. 17FUN04). These projects received funding from the European Metrology Programme for Innovation and Research (EMPIR) cofinanced by the Participating States and from the European Unions Horizon 2020 research and innovation program. H.W.S acknowledges funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy—EXC-2123 QuantumFrontiers No. 390837967. V.K. acknowledges funding by the Latvian Council of Science (Project No. lzp-2018/1-0173). Publisher Copyright: {\textcopyright} 2022 American Physical Society.",
year = "2022",
month = may,
day = "20",
doi = "10.1103/PhysRevB.105.205425",
language = "English",
volume = "105",
journal = "Physical Review B",
issn = "2469-9950",
publisher = "American Institute of Physics",
number = "20",
}