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arXiv · 2309.04930

Deterministic and non-volatile switching of all-van der Waals spin-orbit torque system above room temperature without external magnetic fields

Abstract

Two-dimensional van der Waals (vdW) magnetic materials hold promise for the development of high-density, energy-efficient spintronic devices for memory and computation. Recent breakthroughs in material discoveries and spin-orbit torque (SOT) control of vdW ferromagnets have opened a path for integration of vdW magnets in commercial spintronic devices. However, a solution for field-free electric control of perpendicular magnetic anisotropy (PMA) vdW magnets at room temperatures, essential for building compact and thermally stable spintronic devices, is still missing. Here, we report the first demonstration of field-free deterministic and non-volatile switching of a PMA vdW ferromagnet, Fe$_3$GaTe$_2$ above room temperature (up to 320 K). We use the unconventional out-of-plane anti-damping torque from an adjacent WTe$_2$ layer to enable such switching with a low current density of $2.23 \times 10^6$ A/cm$^2$. This study exemplifies the efficacy of low-symmetry vdW materials for spin-orbit torque control of vdW ferromagnets and provides an all-vdW solution for the next generation of scalable and energy-efficient spintronic devices.

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Shivam N. Kajale, Thanh Nguyen, Mingda Li, Deblina Sarkar. 2023-09-10. Deterministic and non-volatile switching of all-van der Waals spin-orbit torque system above room temperature without external magnetic fields. https://doi.org/10.1126/sciadv.adk8669

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