Suppression of writing error in a spin-orbit magnetization switching device using fieldlike torque
Phys. Rev. B 112, 014411 – Published 7 July, 2025
DOI: https://doi.org/10.1103/yngx-z13v
Abstract
Spin-orbit torque (SOT) induced magnetization switching has attracted attention because of its applicability to a fast writing method in nonvolatile memory. However, it has been clarified that the magnetization switching is sensitive to the current density, the magnetic field strength, and the initial condition, even at zero temperature due to back switching, where the magnetization moves close to the switched state in the presence of SOT but is back to the initial state after turning off the current. Here, we study the SOT-driven magnetization switching probability at finite temperature through numerical simulation of the Landau-Lifshitz-Gilbert equation. The switching probability decreases as the electric current density increases, which is in contrast to that found in the conventional spin-transfer torque devices. The decrease of the switching probability originates from the combination of the back switching and thermal fluctuation. It is found that the switching probability can be kept high when fieldlike torque with an appropriate value is introduced. The analysis on the temporal dynamics indicates that the presence of the fieldlike torque leads to an effective enhancement of the damping torque and results in a fast relaxation to the switched state, which helps to avoid the back switching.
