Fast and accurate Cooper pair pump

TL;DR

This paper introduces a method combining topological properties and quantum control techniques to enable fast, accurate, and perfectly quantized charge pumping in superconducting nanocircuits, with potential applications in quantum metrology.

Contribution

It presents a novel approach using shortcuts to adiabaticity for precise charge pumping at finite speeds, improving accuracy significantly in a three-Josephson junction system.

Findings

Achieves near-perfect quantized charge transfer at finite speeds

Demonstrates order-of-magnitude accuracy improvements in a realistic system

Discusses potential applications in quantum metrology

Abstract

We propose a method to perform accurate and fast charge pumping in superconducting nanocircuits. Combining topological properties and quantum control techniques based on shortcuts to adiabaticity, we show that it is theoretically possible to achieve perfectly quantised charge pumping at any finite-speed driving. Model-specific errors may still arise due the difficulty of implementing the exact control. We thus assess this and other practical issues in a specific system comprised of three Josephson junctions. Using realistic system parameters, we show that our scheme can improve the pumping accuracy of this device by various orders of magnitude. Possible metrological perspectives are discussed.