A hybrid metal/semiconductor electron pump for quantum metrology

TL;DR

This paper introduces a hybrid metal/semiconductor electron pump that achieves high accuracy and robustness at 650MHz, advancing quantum metrology and the realization of a quantum ampere.

Contribution

It presents a novel hybrid transistor pump combining metal and silicon technologies, demonstrating high-frequency, accurate electron pumping suitable for quantum metrology.

Findings

Pumped current shows 5e-4 deviation from theoretical value.

Operates robustly at 650MHz and 0.5K temperature.

Compatible with industrial CMOS processes.

Abstract

Electron pumps capable of delivering a current higher than 100pA with sufficient accuracy are likely to become the direct mise en pratique of the possible new quantum definition of the ampere. Furthermore, they are essential for closing the quantum metrological triangle experiment which tests for possible corrections to the quantum relations linking e and h, the electron charge and the Planck constant, to voltage, resistance and current. We present here single-island hybrid metal/semiconductor transistor pumps which combine the simplicity and efficiency of Coulomb blockade in metals with the unsurpassed performances of silicon switches. Robust and simple pumping at 650MHz and 0.5K is demonstrated. The pumped current obtained over a voltage bias range of 1.4mV corresponds to a relative deviation of 5e-4 from the calculated value, well within the 1.5e-3 uncertainty of the measurement setup. Multi-charge pumping can be performed. The simple design fully integrated in an industrial CMOS process makes it an ideal candidate for national measurement institutes to realize and share a future quantum ampere.