Josephson Current Anomalies in Spin-Orbit Nanowires

We study the anomalous Josephson effect in a nanowire with Rashba spin-orbit interaction and Zeeman spin splitting, contacted with two s-wave superconducting leads with either one or two open conducting channels in the wire. In both cases, we find that the Josephson current is zero at a value φ
₀
≠ 0, π of the phase difference between the order parameter of the leads. While in the former case the critical current is direction independent, in the latter case we observe an asymmetry between I
_c+
(the maximum Josephson current from left to right) and I
_c
- up to about 20%.