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Sextets in four-terminal Josephson junctions

Miriam Rike Ebert1, David Christian Ohnmacht1,*, Wolfgang Belzig1, and Juan Carlos Cuevas2,3

  • *Contact author: david.ohnmacht@uni-konstanz.de
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Phys. Rev. B 112, 195430 – Published 19 November, 2025

DOI: https://doi.org/10.1103/phvj-vfnx

Abstract

Multiterminal superconducting junctions have revitalized the investigation of the Josephson effect. One of the most interesting aspects of these hybrid systems is the occurrence of multi-Cooper pair tunneling processes that have no analog in two-terminal devices. Such correlated tunneling events are also intimately connected to the Andreev bound states (ABSs) supported by these structures. Josephson junctions with four superconducting terminals have attracted special attention because they are predicted to support ABSs with nontrivial topological properties. Here, we present a theoretical study of sextets, which are correlated tunneling processes involving three Cooper pairs and four different superconducting terminals. We investigate how sextets can be identified from the analysis of the current-phase relation, show how sextets are connected to the hybridization of ABSs, and discuss their existence in recent experiments on four-terminal devices realized in hybrid Al/InAs heterostructures.

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synopsis

Six Electrons Tunnel as One

Published 19 November, 2025

Simultaneous tunneling of three electron pairs may occur in some superconducting devices.

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Outline

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Phys. Rev. B 112, 195430– Published 19 November, 2025
  • Received 31 July 2025
  • Accepted 26 September 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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