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Co nanowires have been electroplated into porous Al2O3 templates. The crystalline structure and magnetic properties of Co nanowires of diameters 65 and 200 nm have been studied. Long single crystal Co segments with a hexagonal closed-packed (hcp) structure have been found in the 65 nm-thick nanowires. A mixture of face-centered cubic and hcp single crystal Co segments was observed in the 200 nm-thick nanowires. This finding suggests that the small template pore size favors the growth of hcp Co phase. Magnetic force microscopy measurements showed longitudinal spontaneous magnetic moments in the 65 nm-thick nanowires and transverse moments in the 200 nm-thick nanowires. [ABSTRACT FROM AUTHOR]

Abstract: We fabricate single-crystal Pb, Sn, and Zn nanowires, of length 6 or 60μm and diameter 30–250nm, using an in situ template-based electrochemical method. In this approach, a single nanowire is formed in contact with a pair of bulk film electrodes of Au, Sn, or Pb. We observe that, with superconducting electrodes having a higher critical temperature T c , superconductivity is induced in Sn and Zn nanowires at the T c of the electrodes for nanowires as long as 60μm. With Au electrodes, superconductivity is suppressed completely in 6μm-long nanowires and partially in 60μm-long nanowires. Based on transmission electron microscopy studies, the nanowires are single crystalline. Analysis of the temperature dependence of the normalized resistance suggests that the residual-resistance-ratio plays an important role in the observed anomalous long-range proximity effect. [Copyright &y& Elsevier]

Abstract: An in situ template-based electrochemical method was used to fabricate single-crystal Sn nanowires, of 6μm in length and 30–200nm in diameter, in contact with two bulk film electrodes of Au, Sn, or Pb. Superconductivity in these Sn nanowires was found to depend strongly on the electrode materials. [Copyright &y& Elsevier]

Abstract: Bi nanowires were electrochemically deposited into porous polycarbonate membranes of thickness 6μm and nominal pore diameter 80nm. They have the rhombohedral lattice structure of bulk Bi at ambient pressure. Resistance measurements on single Bi nanowires show evidence for superconductivity below 0.64K. [Copyright &y& Elsevier]