1202.0438 (A. Zazunov et al.)

Supercurrent blockade in Josephson junctions with a Majorana wire    [PDF]

A. Zazunov, R. Egger

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
\pi-periodic behavior with negative critical current for weak tunnel couplings.
Charging effects then cause the anomalous CPR $I(\varphi)=I_c \cos\varphi$,
where the parity-sensitive critical current I_c provides a signature for
Majorana states.

View original: http://arxiv.org/abs/1202.0438