Robust operation of a GaAs tunable barrier electron pump

TL;DR

This paper demonstrates a gallium arsenide tunable-barrier single-electron pump operating with high accuracy at relatively high temperature, showing robust quantization plateaus across multiple control parameters, advancing practical current standards.

Contribution

It provides the first demonstration of a GaAs tunable-barrier electron pump with 1 ppm accuracy at 1.3 K, highlighting robustness and potential for practical applications.

Findings

Achieved 1 ppm accuracy at 1.3 K and 500 MHz

Observed robust quantization plateaus across control parameters

Electron capture occurs in decay-cascade regime

Abstract

We demonstrate the robust operation of a gallium arsenide tunable-barrier single-electron pump operating with 1 part-per-million accuracy at a temperature of $1.3$~K and a pumping frequency of $500$~MHz. The accuracy of current quantisation is investigated as a function of multiple control parameters, and robust plateaus are seen as a function of three control gate voltages and RF drive power. The electron capture is found to be in the decay-cascade, rather than the thermally-broadened regime. The observation of robust plateaus at an elevated temperature which does not require expensive refrigeration is an important step towards validating tunable-barrier pumps as practical current standards.