Spin Hall nano-oscillators based on synthetic skyrmions imprinted in Co nanodisc

Abstract

Spin Hall nano-oscillators utilizing the synthetic spin textures imprinted in nanomagnets are demonstrated by numerical investigations. The imprinting is achieved by locally manipulating the magnetic anisotropy and the interfacial Dzyaloshinskii-Moriya interaction (DMI). The resulting spin texture is equivalent to a Néel-type skyrmion and is topologically stable to thermal fluctuations at finite temperatures. The eigenoscillation of the synthetic skyrmion can be activated by the spin-orbit torques induced by the spin Hall effect, and an eigenfrequency of up to ∼1.5 GHz is achieved. The eigenmode of the skyrmion resonance is found to be associated with the counter-clockwise rotational motion of the local magnetization. Our result demonstrates the working principle of using synthetic nanomagnets in spintronics applications.