On the effect of van Hove singularities on the critical current of high- junctions
School of Physics and Astronomy,
University of Tel-Aviv - Tel-Aviv, Israel
2 Physique et Modélisation, CNRS/Université Joseph Fourier BP 166, 38042 Grenoble, France
Accepted: 25 October 1999
We show that the Josephson critical current between two 2-dimensional super conductors can be strongly affected by the Van Hove singularity of the density of states characteristic of 2-dimensional metals. In particular, when the Fermi level falls at the singularity, the critical current is zero for certain crystallographic misorientations between the two superconductors. This effect sems to have been observed recently in high- grain boundary junction experiments.
PACS: 74.25.Jb – Electronic structure / 74.50.+r – Proximity effects, weak links, tunneling phenomena, and Josephson effects / 74.80.Fp – Point contacts; SN and SNS junctions
© EDP Sciences, 2000