C-axis Resistivity and Magnetoresistance of the Electron-doped Cuprate Pr$_{1.85}$Ce$_{0.15}$CuO$_{4}$

C-axis resistivity and magnetoresistance have been studied extensively in the hole-doped high temperature superconductors. Observations, such as a resistivity upturn and associated negative magnetoresistance (n-MR), were attributed to the pseudogap. Recently similar phenomena were reported in the electron-doped superconductor Sm$_{1.85}$Ce$_{0.15}$CuO$_{4}$ (SCCO), and a universal Zeeman splitting of a spin gap (pseudogap) state was proposed $^1$. Here we report transport properties of Pr$_{1.85}$Ce$_{0.15}$CuO$_{4}$ (PCCO) ($T_C\approx 25K$) single crystals for comparison. Our c-axis n- MR can be explained by superconducting fluctuations due to the Aslamazov-Larkin (AL) process and the fluctuating electronic density of states (FDOS) above $H_{C2}$. We find that PCCO does not follow the Zeeman scaling behavior as reported for SCCO. This work is supported by NSF (Grant DMR 0352735). $^1$ T. Kawakami et al., Phys. Rev. Lett. 95, 017001 (2005).