Effect of magnetic impurities on fluctuations in superconducting films above Tc

We calculate the effect of magnetic impurities on the excess tunneling current, caused by fluctuations in a Josephson junction. The two metals on opposite sides of the junction have different transition temperatures. At temperatures immediately above the transition temperature Tc of the low-Tc side, the excess current versus voltage is found to have a quasi-Lorentzian shape, exactly as in the absence of pair-breaking mechanisms. However, the pair relaxation frequency is reduced by the pair-breaking mechanism, and the coherence length is enhanced. This causes a detectable diminution in the peak voltage, which can serve as a direct measure of the pair-breaking strength. It is suggested that this effect could be used to probe the critical scattering of conduction-electron spins in the vicinity of the magnetic-ordering temperature.