Critical current behavior in Josephson junctions with the weak ferromagnet PdNi

We have studied the variation in critical current in superconductor/ferromagnet/superconductor Josephson Junctions as a function of ferromagnet thickness using a weakly ferromagnetic alloy Pd₈₂Ni₁₂. Measurements were performed for the thickness range 32--100 nm, over which the critical current density decreases by 5 orders of magnitude. The critical current density oscillates with a period of π×(4.4±0.1) nm, and decays over a characteristic length of 7.7±0.5 nm. There is no evidence of a crossover to a slower decay, which might indicate the presence of long-range spin-triplet pair correlations. We discuss possible reasons for their absence, including the possibility of strong spin-flip scattering in PdNi.