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arXiv · 2012.05596

Observation of Magnetic Droplets in Magnetic Tunnel Junctions

Kewen Shi·Wenlong Cai·Sheng Jiang·Daoqian Zhu·Kaihua Cao·Zongxia Guo·Jiaqi Wei·Ao Du·Zhi Li·Yan Huang·Jialiang Yin·Johan Akerman·Weisheng Zhao
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Abstract

Magnetic droplets, a class of highly non-linear magnetodynamical solitons, can be nucleated and stabilized in nanocontact spin-torque nano-oscillators where they greatly increase the microwave output power. Here, we experimentally demonstrate magnetic droplets in magnetic tunnel junctions (MTJs). The droplet nucleation is accompanied by a power increase of over 300 times compared to its ferromagnetic resonance modes. The nucleation and stabilization of droplets are ascribed to the double-CoFeB free layer structure in the all-perpendicular MTJ which provides a low Zhang-Li torque and a high pinning field. Our results enable better electrical sensitivity in the fundamental studies of droplets and show that the droplets can be utilized in MTJ-based applications.

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Kewen Shi, Wenlong Cai, Sheng Jiang, Daoqian Zhu, Kaihua Cao, Zongxia Guo, Jiaqi Wei, Ao Du, Zhi Li, Yan Huang, Jialiang Yin, Johan Akerman, Weisheng Zhao. 2020-12-10. Observation of Magnetic Droplets in Magnetic Tunnel Junctions. https://arxiv.org/abs/2012.05596

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