Deterministic switching of a perpendicularly polarized magnet using unconventional spin–orbit torques in WTe2
Source abstract
Abstract
Spin-orbit torque (SOT)-driven deterministic control of the magnetic state of a ferromagnet with perpendicular magnetic anisotropy is key to next-generation spintronic applications including non-volatile, ultrafast and energy-efficient data-storage devices. However, field-free deterministic switching of perpendicular magnetization remains a challenge because it requires an out-of-plane antidamping torque, which is not allowed in conventional spin-source materials such as heavy metals and topological insulators due to the system's symmetry. The exploitation of low-crystal symmetries in emergent quantum materials offers a unique approach to achieve SOTs with unconventional forms. Here we report an experimental realization of field-free deterministic magnetic switching of a perpendicularly polarized van der Waals magnet employing an out-of-plane antidamping SOT generated in layered WTe2, a quantum material with a low-symmetry crystal structure. Our numerical simulations suggest that the out-of-plane antidamping torque in WTe2 is essential to explain the observed magnetization switching.
Source: europepmc · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Magnetic properties of thin films · 2D Materials and Applications · Advanced Condensed Matter Physics
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (30)
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