Magnetic proximity effect in Pt/α-Fe2O3 bilayers*

Recently antiferromagnetic insulators play an import role in spintronic research including the spin superfluid [1] and long distance spin transport [2]. In this work, we find the magnetic proximity effect (MPE) in non-magnet Pt on antiferromagnetic insulator α-Fe2O3 bilayers. Off-axis sputtering was used to grow the high-quality bilayers as confirmed by atomic force microscopy and X-ray diffraction. Magneto-transport reveals anomalous hall signals at different temperature is observed. To elucidate these features, angle-dependent magnetoresistance (ADMR) measurements at different magnetic fields and temperatures have been conducted to isolate the contributions of anisotropic magnetoresistance (AMR) and spin Hall magnetoresistance (SMR). We also find non-trivial MR signals from field sweeps that reflect novel surface magnetism from the uncompensated moments in α-Fe2O3.

[1] Yuan, Wei, et al. "Experimental signatures of spin superfluid ground state in canted antiferromagnet Cr2O3 via nonlocal spin transport." Science advances 4.4 (2018): eaat1098.
[2] Lebrun, R., et al. "Tunable long-distance spin transport in a crystalline antiferromagnetic iron oxide." Nature 561.7722 (2018): 222.