Resolution of spin Hall and anisotropic magnetoresistance in Pt/EuO$_{1-x}$

We report on the angular and field dependence of the magnetoresistance (MR) in bilayers of Pt/EuO_{1-x} thin films, measured in both in-plane and out-of-plane geometries at different temperatures (T). Presence of oxygen vacancies manifested by a metal-insulator transition as well as a high-T ferromagnet to paramagnet transition (T_P) were observed in the bilayers. The Anisotropic Magnetoresistance (AMR) could be extracted in the entire T-range, even above T_P, exhibiting two sign crossovers. We attribute its T-evolution to the rotation of easy axis direction from a high-T out-of-plane to a low-T in-plane orientation. In addition, considering MR contributions from the films' (111) texture and interface, we identify a T-window wherein the spin Hall effect induced spin Hall magnetoresistance (SMR) could be extracted.

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