Electric properties of metallic nanowires obtained in quantum vortices of superfluid helium

Laser ablation of metals in superfluid helium has been used to obtain nickel, indium, and lead nanowire bundles. Wires 5-8 nm in diameter demonstrate metallic conductivity and are coupled with one another by point contacts. It is shown that the wire bundles attach to sharp tips introduced into the region of condensation and are up to 1 cm long. The high intensity and low threshold of electron field emission are explained by the smallness of the radius of individual wires and the long length of a bundle. The superconducting transition temperature is shifted downwards by 2.9 K in lead nanowires and upwards by more than 1 K in indium nanowires. (c) 2010 American Institute of Physics. [doi:10.1063/1.3481303]