Synthesis and characterization of superconducting single-crystal Sn nanowires

Single-crystal superconducting tin nanowires with diameters of 40-160 nm have been prepared by electrochemical deposition in porous polycarbonate membranes. Structural characterization through transmission electron microscopy and x-ray diffraction showed that the nanowires are highly oriented along the [100] direction. Although the superconducting transition temperature is close to the bulk value of 3.7 K, the effect of reduced dimensionality is clearly evident in the electrical transport properties of the thinnest wires (40 nm diameter). Magnetization measurements show that the critical field of the nanowires increases significantly with decreasing diameter to similar to0.3 T for the thinnest wires, nearly an order of magnitude larger than the bulk value. (C) 2003 American Institute of Physics.