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Vol. 6 No. 4 (2014)

Role of TbFe on Perpendicular Magnetic Anisotropy and Giant Magnetoresistance Effect in [Co/Ni]N-Based Spin Valves

https://doi.org/10.1007/s40820-014-0009-1
Minghong Tang
Department of Optical Science and Engineering, Shanghai Ultra- Precision Optical Engineering Center, Fudan University, Shanghai 200433, People’s Republic of China
Zongzhi Zhang
Department of Optical Science and Engineering, Shanghai Ultra- Precision Optical Engineering Center, Fudan University, Shanghai 200433, People’s Republic of China
Yanyan Zhu
Department of Optical Science and Engineering, Shanghai Ultra- Precision Optical Engineering Center, Fudan University, Shanghai 200433, People’s Republic of China
Bin Ma
Department of Optical Science and Engineering, Shanghai Ultra- Precision Optical Engineering Center, Fudan University, Shanghai 200433, People’s Republic of China
Qinyuan Jin
State Key Laboratory of Precision Spectroscopy and Department of Physics, East China Normal University, Shanghai 200062, People’s Republic of China

Corresponding Author: Zongzhi Zhang

zzzhang@fudan.edu.cn

Nano-Micro Letters, Vol. 6 No. 4 (2014), Article Number: 359-364

Abstract

The exchange-coupled [Co/Ni]N/TbFe nano-magnetic films can display strong perpendicular magnetic anisotropy (PMA) which depends on the Tb:Fe component ratio, TbFe layer thickness and the repetition number N of [Co/Ni]N multilayer. Perpendicular spin valves in the nano thickness scale, consisting of a [Co/Ni]3 free and a [Co/Ni]5/TbFe reference multilayer, show high giant magnetoresistance (GMR) signal of 6.5 % and a large switching field difference over 3 kOe. However, unexpected slanting of the free layer magnetization, accompanied by a reduced GMR ratio, was found to be caused by the presence of a thick Fe-rich or even a thin but Tb-rich TbFe layer. We attribute this phenomenon to the large magnetostriction effect of TbFe which probably induces strong stress acting on the free layer and hence reduces its interfacial PMA.

Keywords

Nano magnetic films Perpendicular magnetic anisotropy Spin valves TbFe
Tang, Minghong, Zongzhi Zhang, Yanyan Zhu, Bin Ma, and Qinyuan Jin. 2014. “Role of TbFe on Perpendicular Magnetic Anisotropy and Giant Magnetoresistance Effect in [Co/Ni]N-Based Spin Valves”. Nano-Micro Letters 6 (4):359-64. https://doi.org/10.1007/s40820-014-0009-1.
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