Electrical manipulation of spins is essential to design state-of-the-art spintronic devices and commonly relies on the spin current injected from a second heavy-metal material. The fact that chiral antiferromagnets produce spin current inspires us to explore the magnetization switching of chiral spins using self-generated spin torque. Here, we demonstrate the electric switching of noncollinear antiferromagnetic state in Mn3Sn by observing a crossover from conventional spin-orbit torque to the self-generated spin torque when increasing the MgO thickness in Ta/MgO/Mn3Sn polycrystalline films. The spin current injection from the Ta layer can be controlled and even blocked by varying the MgO thickness, but the switching sustains even at a large MgO thickness. Furthermore, the switching polarity reverses when the MgO thickness exceeds around 3 nm, which cannot be explained by the spin-orbit torque scenario due to spin current injection from the Ta layer. Evident current-induced switching is also observed in MgO/Mn3Sn and Ti/Mn3Sn bilayers, where external injection of spin Hall current to Mn3Sn is negligible. The inter-grain spin-transfer torque induced by spin-polarized current explains the experimental observations. Our findings provide an alternative pathway for electrical manipulation of non-collinear antiferromagnetic state without resorting to the conventional bilayer structure.

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We report on the study of charge-spin conversion in sputter-deposited WTex films using harmonic Hall measurements. Strong damping-like (DL) spin–orbit torque (SOT) is observed in WTex thin films with the largest SOT efficiency of 0.67 × 105 Ω−1 m−1 at a WTex thickness of 5 nm, which quickly decreases to around zero as the thickness increases to 10 nm. In comparison, the field-like SOT is around one order smaller than the DL SOT. Making use of the large DL SOT, we realize efficient current-induced perpendicular magnetization switching in WTex/Ti/CoFeB multilayers. Our findings suggest the great potential of sputter-deposited WTex in spintronics applications.

Recently, we have developed a spin Hall magnetoresistance (SMR) sensor using the spin–orbit torque effective field as the built-in linearization mechanism, which allows us to achieve a linear, zero-offset, and low-noise magnetic field sensor without any dedicated magnetic bias. In this work, we examine the response of the SMR sensor to a time-varying magnetic field and demonstrate that its inherent frequency selectivity makes it uniquely suited for applications in eddy current testing. By applying a square wave current to both the coil and the sensor, and with the help of principal component analysis, we show that it is possible to detect surface cracks on an aluminum plate with dimensions down to 0.2 mm, without the need to use any sophisticated detection circuitry.

We have investigated the effect of the Pt composition on the spin-orbit torque in a (Fe 0.8 Mn 0.2 ) 1Àx Pt x single-layer ferromagnet. We observed that while the field-like torque decreases and even reverses sign with increasing the Pt composition, the damping-like torque increases monotonically and reaches 0.99 Oe=ð10 10 A=m 2 Þ in a single-layer (Fe 0.8 Mn 0.2 ) 0.52 Pt 0.48 film. The results corroborate the anomalous Hall effect and surface spin rotation model presented previously, and the relative ratio between the damping-like and field-like torques can be qualitatively understood as the relative phase change in spin-conserving and spin-flip scattering.