Spin Hall magnetoresistance in Pt/hexagonal rare-earth ferrite heterostructures*

Multiferroic materials are promising for spintronic application due to their strongly coupled ferroic orders. Hexagonal rare-earth ferrites (h-RFeO₃) possess ferroelectric and anti-ferromagnetic orders that could modify spin-charge conversion with a large electric polarization. We report measurements of field-dependent and angle-dependent magnetoresistance from Pt/h-RFeO₃ heterostructures at various temperatures. It is found that spin Hall magnetoresistance (SMR) and anisotropic magnetoresistance (AMR) coexist in the bilayers. SMR has a temperature dependence similar with those from Pt/ferromagnetic insulators, but the temperature dependence of AMR reaches local maximum around Neel temperature of h-RFeO₃ and changes sign at lower temperatures. The results are discussed within the frame of SMR theory by considering the magnetocrystalline anisotropy of h-RFeO₃.