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Interface engineering is a promising strategy for controlling the Curie temperature (Tc) and perpendicular magnetic anisotropy (PMA) in magnetic 2D van der Waals (2D vdWs)‐based heterostructures. However, establishing high‐quality interface structures in magnetic 2D vdWs/metal stacks, crucial for maximizing interface effects, remains a significant challenge. Here, a Fe5‐xGeTe2/Pt (F5GT/Pt) prototype with a superior interface quality is achieved using a low‐power physical vapor deposition technique. The magnetic properties of the F5GT/Pt heterostructures are strongly influenced by employing the specific physical deposition method. Stable ferromagnetism at 400 K is observed when depositing Pt atoms with relatively high energy, despite the Tc of pristine F5GT being below 300 K. This unexpected high‐temperature ferromagnetism is attributed to the formation of a ferromagnetic alloy at the interface, commonly present in vdWs‐based stacks fabricated through physical deposition but often overlooked. The deposit of Pt atoms with ultralow energy leads to the formation of a unique Fe5‐xGeTe2/Fe3‐xGeTe2 heterojunction at the interface, significantly enhancing the PMA. This work emphasizes the importance of interface structures in vdWs‐based devices, suggesting that controlling the growth process offers an effective approach to construct and engineer vdWs heterostructures, thus improving the performance and introducing new functionalities to spintronic devices. [ABSTRACT FROM AUTHOR]

Synthetic antiferromagnets (SAFs), formed through an interlayer antiferromagnetic exchange coupling of ferromagnetic layers, exhibit intriguing potential in next‐generation spintronic devices due to the zero net magnetization and the high thermal stability. Compared to ferromagnets that are conventionally widely employed, SAFs are expected to significantly improve the data density and stability due to the suppression of the net stray field. Thus far, it has been well established that the spin‐orbit torque (SOT) switching of SAF requires an in‐plane effective magnetic field to break inversion symmetry and thereby assist the Landau–Lifshitz dynamics. This field can either be externally applied or achieved through the exchange coupling given by an adjacent ferromagnetic layer. Such requirement hinders the application of SAFs since a net magnetization cannot be ruled out. Here, the field‐free SOT switching of an all‐SAF system with a significantly reduced net magnetization is demonstrated. The switching is demonstrated to be robust up to ≈460 K. This work paves the way for the practical applications of the SAFs in the SOT‐based memory devices. [ABSTRACT FROM AUTHOR]

Complex oxides with 4d/5d transition metal ions, e.g., SrRuO3, usually possess strong spin–orbit coupling, which potentially leads to efficient charge‐spin interconversion. As the electrical transport property of SrRuO3 can be readily tuned via structure control, it serves as a platform for studying the manipulation of charge‐spin interconversion. Here, a factor of twenty enhancement of spin–orbit torque (SOT) efficiency via strain engineering in a SrRuO3/Ni81Fe19 bilayer is reported. The results show that an orthorhombic SrRuO3 leads to a higher SOT efficiency than the tetragonal one. By changing the strain from compressive to tensile in the orthorhombic SrRuO3, the SOT efficiency can be increased from an average value of 0.04 to 0.89, corresponding to a change of spin Hall conductivity from 27 to 441 × ħ/e (S cm−1). The first‐principles calculations show that the intrinsic Berry curvature can give rise to a large spin Hall conductivity (SHC) via the strain control, which is consistent with the experimental observations. The results provide a route to further enhance the SOT efficiency in complex oxide‐based heterostructures, which will potentially promote the application of complex oxides in energy‐efficient spintronic devices. [ABSTRACT FROM AUTHOR]

Recently intensive efforts have been devoted to the emerging field of antiferromagnetic (AFM) spintronics, where ferromagnetic electrodes are substituted by antiferromagnets. This study investigates the anisotropic magnetoresistance (AMR) of epitaxial tetragonal antiferromagnetic bimetallic films: Mn2Au and Mn2Au/Fe bilayers. An anomalous AMR effect with additional peaks is observed. This study theoretically and experimentally demonstrates that the AFM spins of Mn2Au can be viewed and controlled at room temperature, and this is achievable with a notably relatively small magnetic field of 200 mT. Strong hybridization between Au and Mn, and strong modification of the intrinsic quadratic anisotropy of Mn2Au from interfacial biquadratic anisotropy result in an additional anomalous AMR component of 1%. The findings suggest that Mn2Au films can be used in room temperature antiferromagnetic spintronics. [ABSTRACT FROM AUTHOR]