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Spin Hall magnetoresistance (SMR) is used to study interfacial magnetic features in La2CoMnO6 (LCMO)/Pt bilayers. LCMO is a ferromagnetic insulator with a Curie temperature Tc = 250 K and a strong magnetic anisotropy that can be tuned by microstructural strain. However, SMR measurements do not show any dependence on the strained state of the LCMO films. In addition, contrary to what may be expected, SMR signal persists above TC exhibiting a strong magnetic field dependence well above the saturation of the magnetization while the typical hysteresis on crossing H = 0 is absent. All these results suggest that the uppermost LCMO interfacial layers are magnetically uncoupled from the rest of the LCMO film and they do not show long range magnetic ordering. This fact is confirmed by a complete scanning transmission electron microscopy study of the interface that makes evident that the last atomic layers of the LCMO film do not contain Co and have a LaMnO3+δ simple perovskite‐like structure with the last atomic layer being lanthanum oxide. The analysis of the experimental results according to recent SMR theories indicates, in fact, that the LCMO interfacial layer behaves as a 2D Heisenberg ferromagnet. [ABSTRACT FROM AUTHOR]

Complex oxide thin films grown by using chemical methods are of strong interest because of their low-cost, environment friendly fabrication and easy scalability. However, their introduction in spintronic applications or magnetic devices is still scarce mainly because of concerns regarding their interfacial quality. Here, we report on the preparation by polymer-assisted-deposition (PAD) of epitaxial La0.92MnO3 (LMO) thin films. We demonstrate that ferromagnetic conducting LMO thin films with smooth surfaces (rms ∼ 0.2 nm) can be prepared by PAD. By means of temperature-dependent broadband ferromagnetic resonance (FMR), we show that the LMO film exhibits a four-fold in-plane anisotropy, with [110] being the easy in-plane axis, compatible with strain release from the rhombohedral bulk phase. It has also been found that the isotropic Gilbert damping, α, determined from the broadening of the FMR linewidth, does not show a relevant extrinsic contribution and it exhibits an intraband-like temperature dependence, i.e. it increases as temperature decreases. By capping LMO thin films with a 10 nm thick Pt layer deposited ex situ, damping is substantially enhanced, from a value at 150 K of αLMO ∼ 1 × 10−2 for the bare LMO film to αLMO+Pt ∼ 2.5 × 10−2 for the Pt capped film. This strong increase of magnetic damping is indicative of the transfer of spin momentum from LMO to the Pt layer by spin pumping. Our results demostrate that LMO films grown by PAD may be used as efficient spin source systems in heterostructures for spintronic devices. [ABSTRACT FROM AUTHOR]