Specific heat evidence for bulk s-wave gap symmetry of optimally electron-dopedPr1.85Ce0.15CuO4 − y superconductors

Abstract

We reanalyze specific heat data for optimally electron-dopedPr1.85Ce0.15CuO4 − y superconductors. The magnetic field dependence of the electronic specificheat in the vortex state does not support d-wave gap symmetry but agreesquantitatively with an s-wave theory. Furthermore, the field dependence at a finitetemperature almost coincides with that for a conventional s-wave superconductor,V i3Si. The present work provides bulk evidence for a nodeless s-wave gap symmetry in optimallyelectron-doped cuprates.