Strain and charge co-mediated magnetoelectric coupling are expected in ultra-thin ferromagnetic/ferroelectric multiferroic heterostructures, which could lead to significantly enhanced magnetoelectric coupling. It is however challenging to observe the combined strain charge mediated magnetoelectric coupling, and difficult in quantitatively distinguish these two magnetoelectric coupling mechanisms. We demonstrated in this work, the quantification of the coexistence of strain and surface charge mediated magnetoelectric coupling on ultra-thin Ni0.79Fe0.21/PMN-PT interface by using a Ni0.79Fe0.21/Cu/PMN-PT heterostructure with only strain-mediated magnetoelectric coupling as a control. The NiFe/PMN-PT heterostructure exhibited a high voltage induced effective magnetic field change of 375 Oe enhanced by the surface charge at the PMN-PT interface. Without the enhancement of the charge-mediated magnetoelectric effect by inserting a Cu layer at the PMN-PT interface, the electric field modification of effective magnetic field was 202 Oe. By distinguishing the magnetoelectric coupling mechanisms, a pure surface charge modification of magnetism shows a strong correlation to polarization of PMN-PT. A non-volatile effective magnetic field change of 104 Oe was observed at zero electric field originates from the different remnant polarization state of PMN-PT. The strain and charge co-mediated magnetoelectric coupling in ultra-thin magnetic/ferroelectric heterostructures could lead to power efficient and non-volatile magnetoelectric devices with enhanced magnetoelectric coupling.

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Complex oxides hosting 4d and 5d cations with significant spin–orbit coupling have recently been shown as promising materials for efficient spin‐charge interconversion. Through interfacing 4d and 5d oxides with magnet layers, a large spin–orbit torque (SOT) is reported. However, a room‐temperature SOT switching of perpendicular magnetization by using these oxides, which is essential for spintronic devices, is not demonstrated. Here, this is addressed yet missing aspect by studying heterostructures comprised of two representative complex oxides (4d SrRuO3 and 5d SrIrO3) and a compensated ferrimagnet FeGd with perpendicular magnetic anisotropy. A room temperature current‐induced SOT switching of perpendicular magnetization in both SrRuO3/FeGd and SrIrO3/FeGd bilayers, with the critical switching current density on the order of 106 A cm−2 is demonstrated. The SOT efficiencies of SrRuO3 and SrIrO3 are further quantified by using harmonic Hall voltage measurements. The results suggest that the strongly correlated oxides could be another promising platform for enabling energy‐efficient spin‐orbitronic applications.

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We present room-temperature measurements of magnon spin diffusion in epitaxial ferrimagnetic insulator MgAl0.5Fe1.5O4 (MAFO) thin films near zero applied magnetic field where the sample forms a multi-domain state. Due to a weak uniaxial magnetic anisotropy, the domains are separated primarily by 180° domain walls. We find, surprisingly, that the presence of the domain walls has very little effect on the spin diffusion – nonlocal spin transport signals in the multi-domain state retain at least 95% of the maximum signal strength measured for the spatially-uniform magnetic state, over distances at least five times the typical domain size. This result is in conflict with simple models of interactions between magnons and static domain walls, which predict that the spin polarization carried by the magnons reverses upon passage through a 180° domain wall.

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