0-π phase shifts in Josephson junctions as a signature for the $s_{+-}-wave pairing

We investigate Josephson junctions with superconducting ferropnictides, both in the diffusive and ballistic limit [1,2,3]. We focus on the proposed s_{+-}-wave state, and find that the relative phase shift intrinsic to the s_{+-}-wave state may provide 0-π oscillations in the Josephson current. This feature can be used to discriminate this pairing state from the conventional s-wave symmetry. The 0-π oscillations appear both as a function of the ratio of the interface resistances for each band and, more importantly, as a function of temperature, which greatly aids in their detection.