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

TL;DR

This paper investigates the c-axis transport properties of Bi2Sr2CaCu2O8+y superconductors, revealing that a BCS d-wave model with coherent tunneling explains quasiparticle and Cooper pair transport at low temperatures.

Contribution

It demonstrates that the BCS d-wave model with resonant impurity scattering and coherent tunneling accurately describes interlayer transport in these superconductors.

Findings

Quasiparticle c-axis conductivity depends on temperature and voltage.

Josephson critical current behavior matches model predictions.

Superconducting gap characteristics are consistent with the BCS d-wave model.

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.