Abstract
We have synthesized indium (In) nanowires in pure form and large scale, encapsulated within insulating ZnS nanotubes, and examined the intrinsic superconductivity in one-dimensional limit. We demonstrate that the property of the superconducting nanowires encapsulated within insulating nanotubes can be controlled down to diameters much smaller than the characteristic lengths. The critical temperature and critical magnetic field of the one-dimensional In nanowires are not affected down to a diameter of 40 nm, almost 10% of the coherence length of bulk In. This study further suggests that superconducting interconnects, with controlled physical properties, in nanocircuits could be achieved by such encapsulation.