Interlayer Transport of Quasiparticles and Cooper pairs in Bi2Sr2CaCu2O8+y Superconductors

Abstract

We study the c-axis transport of stacked, intrinsic junctions in Bi2Sr2CaCu2O8+y single crystals, fabricated by the double-sided ion beam processing technique from single crystal whiskers. Measurements of the I-V characteristics of these samples allow us to obtain the temperature and voltage dependence of the quasiparticle c-axis conductivity in the superconducting state, the Josephson critical current, and the superconducting gap. We show that the BCS d-wave model in the clean limit for resonant impurity scattering with a significant contribution from coherent interlayer tunneling, describes satisfactorily the low temperature and low energy c-axis transport of both quasiparticles and Cooper pairs.

4 pages including 3 figures