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arXiv · 1812.08393

Tunable Angle Dependent Magnetization Dynamics in Ni80Fe20 Nano-cross Structures of Varying Size

Kartik Adhikari·Saswati Barman·Ruma Mandal·Yoshichika Otani·Anjan Barman
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Abstract

We demonstrate a large angular dependence of magnetization dynamics in Ni80Fe20 nano-cross arrays of varying sizes. By subtle variation of the azimuthal angle of an in-plane bias magnetic field, the spin configuration and the ensuing spin-wave dynamics, including mode softening, mode splitting, mode crossover and mode merging, can be drastically varied to the extent that a frequency minimum corresponding to mode softening converts to a mode crossover, various mode splitting and mode crossover disappear and additional mode splitting appears. Numerically simulated spin-wave spectra and phase profiles revealed the nature of various spin-wave modes and the origin of above variation of the dynamics with bias-field angle. All of these above observations are further modified with the variation of dimensions of the nano-cross. The numerically calculated magnetostatic field distributions further supports the variation of dynamics with bias-field angle. These results open a new avenue for engineering the nano-cross based magnetic devices such as magnetic storage, spin-wave logic and on-chip data communication devices.

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Kartik Adhikari, Saswati Barman, Ruma Mandal, Yoshichika Otani, Anjan Barman. 2018-12-20. Tunable Angle Dependent Magnetization Dynamics in Ni80Fe20 Nano-cross Structures of Varying Size. https://doi.org/10.1103/physrevapplied.10.044010

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