Towards single-electron metrology

TL;DR

This paper reviews the current understanding of single-electron transport devices, their potential for high-precision electrical standards, and discusses the principles, limitations, and recent experimental progress in their development.

Contribution

It provides a comprehensive overview of the operation, physical mechanisms, and theoretical modeling of SET devices, highlighting their readiness for metrological applications.

Findings

Intrinsic uncertainty of SET devices is sufficiently low for initial metrological use.

Comparison shows some discrepancies between theory and experiment, guiding future improvements.

Recent experimental results support the feasibility of SET-based electrical standards.

Abstract

We review the status of the understanding of single-electron transport (SET) devices with respect to their applicability in metrology. Their envisioned role as the basis of a high-precision electrical standard is outlined and is discussed in the context of other standards. The operation principles of single electron transistors, turnstiles and pumps are explained and the fundamental limits of these devices are discussed in detail. We describe the various physical mechanisms that influence the device uncertainty and review the analytical and numerical methods needed to calculate the intrinsic uncertainty and to optimise the fabrication and operation parameters. Recent experimental results are evaluated and compared with theoretical predictions. Although there are discrepancies between theory and experiments, the intrinsic uncertainty is already small enough to start preparing for the first SET-based metrological applications.