Scaling the current from a GHz electron pump using a CCC

Abstract

We demonstrate the scaling of the current from a tunable-barrier electron pump using a cryogenic current comparator (CCC) with a turns ratio of 1:22592. The amplified current flows in a calibrated 100 kΩ resistor, and the voltage drop across this resistor is directly compared against a binary Josephson array. The experimental setup constitutes a prototype realization of the metrology triangle proposed more than 15 years ago.