Field-free spin-orbit torque switching in L10-FePt single layer with tilted anisotropy

For real-world applications, it is desirable to realize field-free spin-orbit torque (SOT) switching in thin films with high perpendicular magnetic anisotropy (PMA). In this paper, we report that field-free SOT switching in a L1(0)-FePt single layer with a large switching ratio of 26% is obtained by using a MgO & lang;100 & rang;?8 & DEG;/& lang;100 & rang; miscut substrate. It is found that field-free switching depends on the direction of the imposed pulse current. Only when the electric current is along the y (010)-direction but not along the x (100)-direction does field-free switching happen, which can be attributed to the tilted PMA induced symmetry breaking in the x-z plane. Furthermore, under the field-free condition, our FePt single layer system exhibits stable multi-state magnetic switching behavior and nonlinear synaptic characteristics. This work paves the way to realize field-free SOT switching in the L1(0)-FePt single layer, which will have significant impact on spin memory devices and synaptic electronics.

Automated summary

This paper reports the realization of field-free spin-orbit torque switching with high switching ratio in a L1(0)-FePt single layer. The use of a specific substrate allows for this achievement. It is found that the direction of the applied current is crucial for field-free switching, and this phenomenon is explained by symmetry breaking induced by tilted PMA. Additionally, the FePt single layer exhibits stable multi-state magnetic switching behavior and nonlinear synaptic characteristics under the field-free condition.