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An efficient out-of-plane anti-damping spin–orbit torque (SOT) is in great demand for high-density spintronic devices with perpendicular magnetic anisotropy. Despite its importance, direct realization of such SOT in a single magnetic layer is scarce and has remained challenging. Here, we present experimental evidence uncovering unconventional out-of-plane anti-damping torques in the Co film deposited on the ferroelectric Pb(Mg1/3Nb2/3)O3–Pb0.7Ti0.3O3 (PMN–PT) substrate. We show via spin-torque ferromagnetic resonance that both Rashba- and unconventional-type SOT give rise to a high-efficient charge-to-spin conversion. The strong magnetoelectric effect at the Co/PMN-PT interface allows further directly electric-field control of the conversion.

The temperature-dependent Gilbert damping in Co2FeAl thin film grown on a Pb(Mg1/3Nb2/3)O3-30%PbTiO3 substrate is investigated by the systematic measurement of physical property measurement system (PPMS) on a series of samples with different substrate temperatures. Varying the substrate temperatures from 350 °C to 500 °C, the B2 ordering degrees of Co2FeAl thin films increase, which can lead the Gilbert damping to decrease, indicated by the field-sweep in-plane PPMS measurements. In addition, the measurement result of PPMS demonstrates that the Gilbert damping decreases first with measurement temperature decreasing down to about 150 K, then increases at a measurement temperature of ∼ 50 K, and decreases again with the measurement temperature decreasing. There are two independent damping manners, namely bulk damping and surface damping, which contribute to the Gilbert damping. Moreover, the observed peak of Gilbert damping at ∼ 50 K can be attributed to the spin re-orientation transition at the Co2FeAl surface, which is similar to the result of the effective magnetization as a function of measurement temperature. The result presents the evidence for further studying the Gilbert damping in Co2FeAl thin film.

Magnon-tuning non-volatile magnetic dynamics is investigated in a coZr/pMn-pt structure by measuring ferromagnetic resonance at room temperature. The electric-field control of ferromagnetic resonance shows loop-like behavior, which indicates non-volatile electric-field control of the magnetism. Further, fitting the curves of in-plane rotating angle versus ferromagnetic resonance field under different electric fields shows that the effective magnetic field changes in loop-like manner with the electric field. The resulting change in non-volatile saturation magnetization with electric field is consistent with that of a polarization electric field curve. A 1.04% change of saturation magnetization is obtained, which can be attributed to a magnon-driven magnetoelectric coupling at the CoZr/ PMN-PT interface. This magnon-driven magnetoelectric coupling and its dynamic magnetic properties are significant for developing future magnetoelectric devices.

The rare‐earth metal gadolinium (Gd) is characterized by strong spin‐orbit coupling and a paramagnetic‐to‐ferromagnetic phase transition that enables modulation of a charge–spin conversion via temperature. Charge–spin conversion is experimentally observed and the conversion efficiency is ≈0.26, which is slightly larger than that for Pt and Ta and smaller than that for W. The temperature dependence of charge–spin conversion initially decreases, followed by increasing, because of the paramagnetic‐to‐ferromagnetic phase transition. The charge–spin conversion efficiencies arising from the bulk‐spin Hall effect and the interfacial Rashba–Edelstein effect, respectively, via MgO/Gd/Py and MgO/Py/GdOx systems, are distinguished. The latter has a more significant enhancement because of ambient oxidation that generates the Gd/GdOx interface. The possibility of modulating the conversion efficiency via temperature and oxidation enables applications in spintronic and oxide electronic devices.