We report ferromagnetic resonance in the normal configuration of an electrically insulating magnetic bi-layer consisting of two yttrium iron garnet (YIG) films epitaxially grown on both sides of a 0.5 mm thick non-magnetic gadolinium gallium garnet (GGG) slab. An interference pattern is observed and it is explained as the strong coupling of the magnetization dynamics of the two YIG layers either in-phase or out-of-phase by the standing transverse sound waves, which are excited through the magneto-elastic interaction. This coherent mediation of angular momentum by circularly polarized phonons through a non-magnetic material over macroscopic distances can be useful for future information technologies. arXiv:1905.12523v3 [cond-mat.mes-hall]

We succeeded in fabricating a CoFeB/MgO-based magnetic tunnel junction (MTJ) directly on an organic flexible substrate. The MTJ shows good strain endurance while keeping the tunnel magnetoresistance (TMR) ratio of ∼100% under various strained conditions; the TMR ratio is almost unchanged up to a tensile strain of 1.2%. Because of the magnetoelastic effect, the magnetic anisotropy fields for the top and bottom CoFeB layers are linearly proportional to strain with almost the same rate as that in a single CoFeB film, suggesting that the expected strain is added on both CoFeB layers in the MTJ pillar from the stretched flexible substrate.

No abstract

No abstract

We report that Joule heating can be used to enhance the interfacial spin conductivity between a metal and an oxide. We observe that local annealing of the interface at about 550 K, when injecting large current densities (>1012A/m2) into a pristine 7 nm thick Pt nanostrip evaporated on top of yttrium iron garnet (YIG), can improve the effective spin transmission up to a factor of 3. This result is of particular interest when interfacing ultrathin garnet films to avoid strong chemical etching of the surface. The effect is confirmed by the following methods: spin Hall magnetoresistance, spin pumping, and non-local spin transport. We use it to study the influence of the YIG|Pt coupling on the non-linear spin transport properties. We find that the crossover current from a linear to a non-linear spin transport regime is independent of this coupling.

No abstract

No abstract

No abstract