Absence of nodes in the energy gap of the high-temperature electron-doped Pr1.85Ce0.15CuO4-y superconductor using thermal conductivity and specific heat measurements

We present data analyses of the thermal conductivity and specific heat of electron-doped Pr1.85Ce0.15CuO4-y. The zero-field thermal conductivity and specific heat of this optimally electrondoped system can be only explained by a nodeless gap symmetry. The magnetic-field dependence of the electronic specific heat in the vortex state is in quantitative agreement with an s-wave theory. Our quantitative data analyses provide bulk evidence for a nodeless gap symmetry in optimally electron-doped cuprates.