We use in-plane tunneling spectroscopy to study the temperature dependence of the local superconducting gap Δ(T) in electron-doped copper oxides with various Tc's and Ce-doping concentrations. We show that the temperature dependence of Δ(T) follows the expectation of the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity, where Δ(0)/kBTc≈1.72±0.15 and Δ(0) is the average superconducting gap across the Fermi surface, for all the doping levels investigated. These results suggest that the electron-doped superconducting copper oxides are weak coupling BCS superconductors.
@article{arxiv.cond-mat/0703256,
title = {Weak coupling Bardeen-Cooper-Schrieffer suerconductivity in the Electron-Doped Cuprate Superconductors},
author = {L. Shan and Y. Huang and Y. L. Wang and Shiliang Li and Jun Zhao and Pengcheng Dai and Y. Z. Zhang and C. Ren and H. H. Wen},
journal= {arXiv preprint arXiv:cond-mat/0703256},
year = {2008}
}