Weak-coupling Bardeen-Cooper-Schrieffer superconductivity in the electron-doped cuprate superconductors

We use in-plane tunneling spectroscopy to study the temperature dependence of the local superconducting gap Delta(T) in electron-doped copper oxides with various T-c's and Ce-doping concentrations. We show that the temperature dependence of Delta(T) follows the expectation of the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity, where Delta(0)/k(B)T(c)approximate to 1.72 +/- 0.15 and Delta(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.