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Updated: May 12, 2026

Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains
Published on: July 20, 2022
Spin wave-assisted reduction in switching field of highly coercive iron-platinum magnets
Takeshi Seki1, Kazutoshi Utsumiya, Yukio Nozaki
1Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan. go-sai@imr.tohoku.ac.jp
Abstract:
Recent rapid progress in spintronic and magnetic storage nanodevices has required nanomagnets to balance competing goals for high coercive field and low switching field. However, a decisive route for highly efficient magnetization switching has not been established yet. Here we propose a novel switching method using a spin wave of magnetic structures twisted in a nanometre scale. We have experimentally demonstrated extremely low field-magnetization switching in a highly coercive FePt by using a spin wave excited in a soft magnetic permalloy (Ni81Fe19), where permalloy is exchange-coupled to FePt through the interface. We can tune the switching field by varying the magnitude and frequency of the radio frequency magnetic field, and a significant decrease in switching field by one order of magnitude is achieved under the optimum conditions. The spin wave-assisted magnetization switching is a promising technique for ultralow-energy magnetization manipulation.
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