Low-temperature saturation of the superconducting properties induced in silver by the proximity effect

Critical-field measurements of silver layers sandwiched between two superconducting layers indicate that supercooling appears below a temperature T* and that the supercooling field stays constant at low temperatures. We propose a simple theoretical model which correctly predicts the temperature of saturation as well as the observed amount of supercooling, and leads to an estimate of 0.1 for NV for silver. This model further suggests that a 1x spatial dependence of the order parameter in the silver should be observed in the He3 temperature range and below.