Non-trivial Chern numbers in three-terminal Josephson junctions

Julia S. Meyer; Manuel Houzet

doi:10.1103/physrevlett.119.136807

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arXiv · 1705.02478

Non-trivial Chern numbers in three-terminal Josephson junctions

Julia S. Meyer·Manuel Houzet

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Abstract

Recently it has been predicted that the Andreev bound state spectrum of 4-terminal Josephson junctions may possess zero-energy Weyl singularities. Using one superconducting phase as a control parameter, these singularities are associated with topological transitions between time-reversal symmetry broken phases with different Chern numbers. Here we show that such topological transitions may also be tuned with a magnetic flux through the junction area in a 3-terminal geometry.

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Julia S. Meyer, Manuel Houzet. 2017-05-06. Non-trivial Chern numbers in three-terminal Josephson junctions. https://doi.org/10.1103/physrevlett.119.136807

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