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We report spin-orbit torque (SOT) in a single ferrimagnetic (FIM) GdFeCo alloy based on spin-torque ferromagnetic resonance (ST FMR). Thickness-dependent anomalous Hall resistance shows a bulk perpendicular magnetic anisotropy, which lead double peaks of ST FMR spectra at a larger thickness of 50 nm. Oblique-angle-dependent ST FMR is performed to study SOT, and the spin torque efficiency in the y axis is evaluated. This phenomenon is explained by the relationship between SOT and saturation magnetization. This finding provides an alternative method to modulate SOT in a single ferrimagnetic spintronic device.

We report on the electric-field-modulated anomalous Hall effect (AHE) under various temperatures in ferrimagnetic GdFeCo/Pb(Mg1/3Nb2/3)0.67Ti0.33O3 (PMN-PT) structures with perpendicular magnetic anisotropy. The coercive field H c and the magnetic compensation temperature T M are modulated by applying an electric field to the multilayer. The resistance ratio (ΔR xy/R xy) plotted as a function of the symmetric bipolar electric field takes the form of a nonvolatile butterfly-like bipolar curve. The resonance field H r of the ferromagnetic resonance spectra as a function of the applied electric field shows a typical butterfly-like shape, indicating that strain is the dominant effect in the electric-field-controlled AHE in the ferrimagnetic heterostructure. In addition, a four-state nonvolatile memory is observed upon simultaneous application of pulsed magnetic field and electric field. The results for the electric-field-controlled AHE should prove useful for research into the development of ultra-energy-efficient ferrimagnets.