Isotropic Ferromagnetic Resonances Induced by Suppressed Anisotropy in Soft Magnetic Microstructures

Lianze Ji,1,2,

Xiaochen Shen,2,3,

Rongzhi Zhao,1,2,*Email

Chenglong Hu,1,2

Xiaoyu Zhao,2

Yixing Li,1

Jian Zhang,2

Wenchao Chen,2

Yimin Chen,1

Jamal Daoud4 

Xuefeng Zhang1,2

1 Key Laboratory for Anisotropy and Texture of Materials (MOE), School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China.

2 Institute of Advanced Magnetic Materials, College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310012, China.

3 Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116023, China.

4 Galenvs Sciences Inc., Quebec, H3E1M3, Canada

These authors contributed equally: L. Ji, X. Shen.

Abstract

The miniaturization of electronic devices has brought new challenges and opportunities due to the appearance of unusual physical effects. Especially, the in-plane anisotropy introduced during the film deposition can be not beneficial for soft magnetic applications. Herein, we demonstrated the suppression of anisotropy in soft magnetic films by constructing quasi-three-dimensional soft magnetic microstructures which include a magnetic dots array in bottom layer and a magnetic antidots array in top layer. It is confirmed that the in-plane anisotropy can be suppressed by the characterization of hysteresis loops, ascribed to the formation of annular stripe domains induced by the competition between exchange energy and demagnetization energy in the dots array. The resonant frequencies of patterned microstructures increase from 1.2 GHz to 3.3 GHz with the increase of external magnetic fields from 32 Oe to 160 Oe. Thus, our results provide an insight for designing tree-dimensional devices without in-plane anisotropy.

Isotropic Ferromagnetic Resonances Induced by Suppressed Anisotropy in Soft Magnetic Microstructures