Anisotropic superconducting-state thermodynamic parameters of the electron-doped compoundSm1.85Ce0.15CuO4−y

The anisotropic superconducting-state thermodynamic parameters of the electron-doped compound ${\mathrm{Sm}}_{1.85}$ ${\mathrm{Ce}}_{0.15}$ ${\mathrm{CuO}}_{4\mathrm{-}\mathit{y}}$ have been derived from reversible dc magnetization M(H,T) measurements on magnetically aligned single-crystal particles of the compound for magnetic fields applied perpendicular and parallel to the ab plane. A recent model developed by Hao et al., which describes M(H,T) over the entire field region between ${\mathit{H}}_{\mathit{c}1}$ and ${\mathit{H}}_{\mathit{c}2}$, was used to analyze the M(H,T) data. The analysis of the measurements provides a self-consistent test of the model and resolves a controversy by showing that the anisotropy of ${\mathit{H}}_{\mathit{c}2}$(T) of the electron-doped compound ${\mathrm{Sm}}_{1.85}$ ${\mathrm{Ce}}_{0.15}$ ${\mathrm{CuO}}_{4\mathrm{-}\mathit{y}}$ is comparable to that of the hole-doped compound ${\mathrm{YBa}}_2$ ${\mathrm{Cu}}_3$ ${\mathrm{O}}_{7\mathrm{-}\mathrm{\delta }}$.