Local electrical tuning of the nonlocal signals in a Cooper pair splitter

Abstract

A Cooper pair splitter consists of a central superconducting contact, S, from which electrons are injected into two parallel, spatially separated quantum dots (QDs). This geometry and electron interactions can lead to correlated electrical currents due to the spatial separation of spin-singlet Cooper pairs from S. We present experiments on such a device with a series of bottom gates, which allows for spatially resolved tuning of the tunnel couplings between the QDs and the electrical contacts and between the QDs. Our main findings are gate-induced transitions between positive conductance correlation in the QDs due to Cooper pair splitting and negative correlations due to QD dynamics. Using a semi-classical rate equation model we show that the experimental findings are consistent with in-situ electrical tuning of the local and nonlocal quantum transport processes. In particular, we illustrate how the competition between Cooper pair splitting and local processes can be optimized in such hybrid nanostructures.

9 pages, 6 figures, 2 tables

References in corpus (7)

• Signatures of Majorana fermions in hybrid superconductor-semiconductor nanowire devices
• Near-unity Cooper pair splitting efficiency
• Superconducting proximity effect in interacting double-dot systems
• Current and noise correlations in a double dot Cooper pair beam splitter
• Proposal for a cumulant-based Bell test for mesoscopic junctions
• Probing individual split Cooper-pairs using the spin qubit toolkit
• Microwave spectroscopy of a Cooper pair beam splitter

Cited by in corpus (4)

• Nonlocal Andreev Entanglements and Triplet Correlations in Graphene with Spin Orbit Coupling
• Double quantum dot Cooper-pair splitter at finite couplings
• Kondo physics in double quantum dot based Cooper pair splitters
• Magnetoresistence engineering and singlet/triplet switching in InAs nanowire quantum dots with ferromagnetic sidegates