Mesoscopic SNS junctions on the basis of superconducting PtSi films

Low-temperature transport measurements on superconducting film - normal met al wire - superconducting film (SNS) junctions fabricated on the basis of 6 nm thick superconducting polycrystalline PtSi films are reported. The stru ctures with the normal metal wires of two different lengths L = 1.5 and 6 u m and the same widths W = 0.3 mu m are studied. The zero bias resistance di p is observed for all junctions whereas the subharmonic energy gap structur e (SGS) originating from multiple Andreev reflections occurs only in the SN S junctions with short wires. (C) 2000 Elsevier Science B.V. All rights res erved.