Magnetic skyrmionium diode with a magnetic anisotropy voltage gating
Junlin Wang, Jing Xia, Xichao Zhang, Xiangyu Zheng, Guanqi Li, Li Chen, Yan Zhou, Jing Wu, Haihong Yin, R.W. Chantrell, Yongbing Xu
Abstract
The magnetic skyrmionium can be seen as a coalition of two magnetic skyrmions with opposite topological charges and has potential applications in next-generation spintronic devices. Here, we report the current-driven dynamics of a skyrmionium in a ferromagnetic nanotrack with the voltage-controlled magnetic anisotropy. The pinning and depinning of a skyrmionium controlled by the voltage gate are investigated. The current-driven skyrmionium can be used to mimic the skyrmionium diode effect in the nanotrack with a voltage gate. We have further studied the skyrmionium dynamics in the nanotrack driven by a magnetic anisotropy gradient in the absence of spin current. The performance of a single wedge-shaped voltage gate at different temperatures is studied. Our results may provide useful guidelines for the design of voltage-controlled and skyrmionium-based spintronic devices.