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arXiv · 2107.03435

Non-Abelian monopoles in the multiterminal Josephson effect

Hong-Yi Xie·Jaglul Hasan·Alex Levchenko
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Abstract

In this work we present a detailed theoretical analysis for the spectral properties of Andreev bound states in the multiterminal Josephson junctions by employing a symmetry-constrained scattering matrix approach. We find that in the synthetic multidimensional space of superconducting phases, crossings of Andreev bands may support non-Abelian SU(2) monopoles with a topological charge characterized by the second class Chern number. We propose that these topological defects can be detected via a nonlinear response measurement of the current autocorrelations. In addition, multiterminal Josephson junction devices can be tested as a hardware platform for realizing holonomic quantum computation.

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Hong-Yi Xie, Jaglul Hasan, Alex Levchenko. 2021-07-07. Non-Abelian monopoles in the multiterminal Josephson effect. https://doi.org/10.1103/physrevb.105.l241404

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