Revealing charge-tunneling processes between a quantum dot and a superconducting island through gate sensing
Jasper Van Veen (TU Delft - QuTech Advanced Research Centre, Kavli institute of nanoscience Delft, TU Delft - QRD/Kouwenhoven Lab)
Damaz De Jong (Kavli institute of nanoscience Delft, TU Delft - QuTech Advanced Research Centre, TU Delft - QRD/Kouwenhoven Lab)
Lin Han (Kavli institute of nanoscience Delft, TU Delft - QuTech Advanced Research Centre, TU Delft - QRD/Kouwenhoven Lab)
Christian Prosko (Kavli institute of nanoscience Delft, TU Delft - QRD/Kouwenhoven Lab, TU Delft - QuTech Advanced Research Centre)
Peter Krogstrup (University of Copenhagen)
John D. Watson (Microsoft Quantum Lab Delft, TU Delft - QRD/Kouwenhoven Lab)
Leo P. Kouwenhoven (TU Delft - QN/Kouwenhoven Lab, Kavli institute of nanoscience Delft, TU Delft - QRD/Kouwenhoven Lab, Microsoft Quantum Lab Delft, TU Delft - QuTech Advanced Research Centre)
Wolfgang Pfaff (Microsoft Quantum Lab Delft, TU Delft - QRD/Kouwenhoven Lab)
More Info
expand_more
Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.
Abstract
We report direct detection of charge tunneling between a quantum dot and a superconducting island through radio-frequency gate sensing. We are able to resolve spin-dependent quasiparticle tunneling as well as two-particle tunneling involving Cooper pairs. The quantum dot can act as an RF-only sensor to characterize the superconductor addition spectrum, enabling us to access subgap states without transport. Our results provide guidance for future dispersive parity measurements of Majorana modes, which can be realized by detecting the parity-dependent tunneling between dots and islands.