Stabilization of single-electron pumps by high magnetic fields

TL;DR

Applying high magnetic fields to single-electron pumps enhances charge state stability and suppresses nonadiabatic excitations, leading to improved current quantization accuracy in these quantum devices.

Contribution

This study demonstrates that high magnetic fields improve the stability and accuracy of single-electron pumps by affecting tunnel rates and electrostatic sensitivities.

Findings

Enhanced current quantization with high magnetic fields

Suppressed nonadiabatic excitations in electron pumps

Increased stability of charge states under magnetic influence

Abstract

We study the effect of perpendicular magnetic fields on a single-electron system with a strongly time-dependent electrostatic potential. Continuous improvements to the current quantization in these electron pumps are revealed by high-resolution measurements. Simulations show that the sensitivity of tunnel rates to the barrier potential is enhanced, stabilizing particular charge states. Nonadiabatic excitations are also suppressed due to a reduced sensitivity of the Fock-Darwin states to electrostatic potential. The combination of these effects leads to significantly more accurate current quantization.