c-axis longitudinal magnetoresistance of the electron-doped superconductor Pr1.85Ce0.15CuO4

We report c-axis resistivity and longitudinal magnetoresistance measurements of superconducting Pr1.85Ce0.15CuO4 single crystals. In the temperature range 13 <= T <= 32 K, a negative magnetoresistance is observed at fields just above H-C2. Our studies suggest that this negative magnetoresistance is caused by superconducting fluctuations. At lower temperatures (T <= 13 K), a different magnetoresistance behavior and a resistivity upturn are observed, whose origin is still unknown.