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Low temperature conductance fluctuations in individual InAs nanowires are studied as a function of gate potential, magnetic field, and the angle between the field and the nanowire axis. The fluctuation pattern as a function of magnetic field shows a reduced flux pickup as the angle is varied from perpendicular to parallel. Statistically independent traces for each angle were measured and the angle dependence of the average correlation field is compared to theory. The results are consistent with the predictions for a geometry where electrons occupy the entire sample volume rather than a surface electron gas as has been speculated. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]