Construction of a Cantilever-Andreev-Tunneling rig and its applications to superconductors

Abstract

A technique for point-contact spectroscopy, based on an electro-mechanical mechanism for the contact formation, has been developed. It is designed to be used in both ${}^4$He and ${}^3$He cryostats. The performance has been demonstrated by conductance measurements on various kinds of superconductors, including the conventional superconductor Nb, the two-band superconductor MgB${}_2$, and the heavy-fermion superconductor CeCoIn${}_5$. Characteristic conductance spectra obtained prove this technique is useful for the investigation of the superconducting order parameter. Advantages of this technique such as its simplicity and versatility are described.

7 Pages, 7 figures, typeset in LaTeX, submitted to Rev. Sci. Instrum