Experimental Study of the Proximity Effect in Thin-Film Heterostructures with the Superconducting Lead Layerof Variable Thickness

A systematic study is performed of the superconductor/normal metal, superconductor/antiferromagnet, and superconductor/ferromagnet proximity effects in structures with superconducting lead layers of variable thickness. It is shown that temperature Ts of the superconducting transition in these systems behaves differently when the superconducting layer is thinned. In superconductor/antiferromagnet structures, Ts changes negligibly within the investigated range of lead layer thickness. Ratio RRR (R300 K/R10 K) of electrical resistance falls notably as the lead layer thins, which could indicate a growing contribution from surface defects. The width of superconducting transitions grows as the lead layer thins, testifying to size effects.