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arXiv · 2005.11848

Quantum-Dot Parity Effects in Trivial and Topological Josephson Junctions

D. Razmadze·E. C. T. O'Farrell·P. Krogstrup·C. M. Marcus
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Abstract

An odd-occupied quantum dot in a Josephson junction can flip transmission phase, creating a {\pi}-junction. When the junction couples topological superconductors, no phase flip is expected. We investigate this and related effects in a full-shell hybrid interferometer, using gate voltage to control dot-junction parity and axial magnetic flux to control the transition from trivial to topological superconductivity. Enhanced zero-bias conductance and critical current for odd parity in the topological phase reflects hybridization of the confined spin with zero-energy modes in the leads.

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D. Razmadze, E. C. T. O'Farrell, P. Krogstrup, C. M. Marcus. 2020-05-24. Quantum-Dot Parity Effects in Trivial and Topological Josephson Junctions. https://doi.org/10.1103/physrevlett.125.116803

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