Tunable Superconducting Coupling of Quantum Dots via Andreev Bound States in Semiconductor-Superconductor Nanowires

Tunable Superconducting Coupling of Quantum Dots via Andreev Bound States in Semiconductor-Superconductor Nanowires

Liu, C. (TU Delft QRD/Wimmer Group; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft)
Wang, Guanzhong (TU Delft QRD/Kouwenhoven Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft)
Dvir, T. (TU Delft QRD/Kouwenhoven Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft)
Wimmer, M.T. (TU Delft QN/Wimmer Group; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft)

2022

Semiconductor quantum dots have proven to be a useful platform for quantum simulation in the solid state. However, implementing a superconducting coupling between quantum dots mediated by a Cooper pair has so far suffered from limited tunability and strong suppression. This has limited applications such as Cooper pair splitting and quantum dot simulation of topological Kitaev chains. In this Letter, we propose how to mediate tunable effective couplings via Andreev bound states in a semiconductor-superconductor nanowire connecting two quantum dots. We show that in this way it is possible to individually control both the coupling mediated by Cooper pairs and by single electrons by changing the properties of the Andreev bound states with easily accessible experimental parameters. In addition, the problem of coupling suppression is greatly mitigated. We also propose how to experimentally extract the coupling strengths from resonant current in a three-terminal junction. Our proposal will enable future experiments that have not been possible so far.

http://resolver.tudelft.nl/uuid:17dd0e10-330a-4904-b81b-2820c4805b14

https://doi.org/10.1103/PhysRevLett.129.267701

0031-9007

Physical Review Letters, 129 (26)

Institutional Repository

journal article

© 2022 C. Liu, Guanzhong Wang, T. Dvir, M.T. Wimmer