Selective control of conductance modes in multi-terminal Josephson junctions

Gino V Graziano; Mohit Gupta; Mihir Pendharkar; Jason T Dong; Connor P Dempsey; Chris Palmstrøm; Vlad S Pribiag

doi:10.1038/s41467-022-33682-2

Selective control of conductance modes in multi-terminal Josephson junctions

Nat Commun. 2022 Oct 8;13(1):5933. doi: 10.1038/s41467-022-33682-2.

Authors

Gino V Graziano^#¹, Mohit Gupta^#¹, Mihir Pendharkar^{2

3}, Jason T Dong⁴, Connor P Dempsey², Chris Palmstrøm^{2

4

5}, Vlad S Pribiag⁶

Affiliations

¹ School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, 55455, USA.
² Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA.
³ Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA.
⁴ Materials Department, University of California Santa Barbara, Santa Barbara, CA, 93106, USA.
⁵ California NanoSystems Institute, University of California Santa Barbara, Santa Barbara, CA, 93106, USA.
⁶ School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, 55455, USA. vpribiag@umn.edu.

^# Contributed equally.

Abstract

The Andreev bound state spectra of multi-terminal Josephson junctions form an artificial band structure, which is predicted to host tunable topological phases under certain conditions. However, the number of conductance modes between the terminals of a multi-terminal Josephson junction must be few in order for this spectrum to be experimentally accessible. In this work, we employ a quantum point contact geometry in three-terminal Josephson devices to demonstrate independent control of conductance modes between each pair of terminals and access to the single-mode regime coexistent with the presence of superconducting coupling. These results establish a full platform on which to realize tunable Andreev bound state spectra in multi-terminal Josephson junctions.

Abstract

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