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arXiv · 1808.05837

Supercurrent in a double quantum dot

J. C. Estrada Saldaña·A. Vekris·G. Steffensen·R. Žitko·P. Krogstrup·J. Paaske·K. Grove-Rasmussen·J. Nygård
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Abstract

We demonstrate the Josephson effect in a serial double quantum dot defined in a nanowire with epitaxial superconducting leads. The supercurrent stability diagram adopts a honeycomb pattern with electron-hole and left-right reflection symmetry. We observe sharp discontinuities in the magnitude of the critical current, $I_c$, as a function of dot occupation, related to doublet to singlet ground state transitions. Detuning of the energy levels offers a tuning knob for $I_c$, which attains a maximum at zero detuning. The consistency between experiment and theory indicates that our device is a faithful realization of the two-impurity Anderson model.

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J. C. Estrada Saldaña, A. Vekris, G. Steffensen, R. Žitko, P. Krogstrup, J. Paaske, K. Grove-Rasmussen, J. Nygård. 2018-08-17. Supercurrent in a double quantum dot. https://doi.org/10.1103/physrevlett.121.257701

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