Investigation of the Superconducting Energy Gap Behavior of Single Crystal Rhenium by Tunneling

摘要

A 15.7% anisotropy in the superconducting energy gap has been measured by electron tunneling into single crystals of rhenium, using thin carbon films as the tunneling barrier to form Re-C-In sandwiches. The energy gap behavior with temperature is BCS-like. The anisotropy agrees with ultrasonic measurements of other hcp metals and suggests that phonon dispersion plays a dominating role in the gap behavior. However, gap values determined from multiparticle tunneling data exhibited reduced gap magnitudes, and a dissimilar crystallographic behavior. (Author)