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arXiv · 1202.0438

Supercurrent blockade in Josephson junctions with a Majorana wire

A. Zazunov·R. Egger
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Abstract

We study the Josephson effect for a topologically nontrivial superconducting (TS) wire with Majorana fermion end states and tunnel-coupled to s-wave BCS superconducting (S) electrodes. In an S-TS junction, no supercurrent flow is possible under fairly general conditions. For the S-TS-S junction, bulk TS quasiparticles must be accessible to have a Josephson effect. In the noninteracting case, we derive the exact current-phase relation (CPR) and find π-periodic behavior with negative critical current for weak tunnel couplings. Charging effects then cause the anomalous CPR $I(φ)=I_c \cosφ$, where the parity-sensitive critical current I_c provides a signature for Majorana states.

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A. Zazunov, R. Egger. 2012-03-13. Supercurrent blockade in Josephson junctions with a Majorana wire. https://doi.org/10.1103/physrevb.85.104514

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