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arXiv · 1904.10472

Topological phase diagram of a three-terminal Josephson junction: From the conventional to the Majorana regime

Lucila Peralta Gavensky·Gonzalo Usaj·Carlos A. Balseiro
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Abstract

We study the evolution of averaged transconductances in three-terminal Josephson junctions when the superconducting leads are led throughout a topological phase transition from an $s$-wave to a $p$-wave (Majorana) phase by an in-plane magnetic field $B_x$. We provide a complete description of this transition as a function of $B_x$ and a magnetic flux $Φ$ threading the junction. For that we use a spinful model within a formalism that allows to treat on equal footing the contribution to the transconductance from both the Andreev subgap levels and the continuum spectrum. We unveil a fractionalization in the quantization of the transconductance due to the presence of Majorana quasiparticles, reflecting the effective pumping of half a Cooper pair charge in the $p$-wave regime.

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Lucila Peralta Gavensky, Gonzalo Usaj, Carlos A. Balseiro. 2019-07-16. Topological phase diagram of a three-terminal Josephson junction: From the conventional to the Majorana regime. https://doi.org/10.1103/physrevb.100.014514

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