We briefly review results of recent neutron scattering and STM experiments designed to probe the relationship between electron-pairing and magnetism in the electron-doped Pr0.88LaCe0.12CuO4 as the system is tuned from its as-grown
non-superconducting antiferromagnetic (AF) state into an optimally doped superconductor (Tc = 26 K) without static AF order [1-7]. As grown, electron-doped materials are semiconducting with static long-range AF order, annealing the sample in low oxygen environment removes the static AF order and induces superconductivity. On the other hand, application of a magnetic field can also induce superconductivity-normal phase transition. In this talk, I will summarize
how one can use annealing and magnetic field as tuning parameters to study the superconducting-normal phase transition. We compare our neutron scattering results with STM results on the same sample and demonstrate that AF spin fluctuations may mediate electron pairing for superconductivity.

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