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Temperature dependence of static and dynamic magnetic properties in NiFe/IrMn bilayer system

Published online by Cambridge University Press:  10 June 2014

Faris Basheer Abdulahad ,
Dung-Shing Hung Open the ORCID record for Dung-Shing Hung [Opens in a new window]  and
Shang-Fan Lee
Faris Basheer Abdulahad
Affiliation:
Institute of Physics, Academia Sinica, Taipei 11529, Taiwan; Nano Science and Technology Program, TIGP, Academia Sinica, Taipei 11529, Taiwan; and Department of Engineering and System Science, National Tsing Hua University, Hsinchu 300, Taiwan
Dung-Shing Hung
Affiliation:
Department of Information and Telecommunications Engineering, Ming Chuan University, Taipei 111, Taiwan
Shang-Fan Lee*
Affiliation:
Institute of Physics, Academia Sinica, Taipei 11529, Taiwan; and Nano Science and Technology Program, TIGP, Academia Sinica, Taipei 11529, Taiwan
*
a)Address all correspondence to this author. e-mail: leesf@phys.sinica.edu.tw
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Abstract

A systematic experimental study on the exchange bias (EB) effect in a ferromagnet/antiferromagnet bilayer system is performed both in the static (dc) and dynamic (high frequency) timescale to clarify the effects of temperature and antiferromagnetic (AFM) layer thickness on the system's stability and magnetic properties. Our system consists of NiFe/IrMn. Both parallel and perpendicular domain walls are suggested to explain the static EB and coercivity behaviors. In the microwave region, peaks, which can only be suppressed at high temperatures with strong external fields, were observed in the AFM thickness dependencies of the dynamic effective field and resonance frequency. The temperature dependence of both static and dynamic parameters suggests different values of Néel temperatures. The dynamic results show a rotatable anisotropy contribution, which has a peak value at the blocking temperature and vanishes at the dynamic Néel temperature.

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Articles
Information
Journal of Materials Research , Volume 29 , Issue 11 , 14 June 2014 , pp. 1237 - 1247
Copyright
Copyright © Materials Research Society 2014 

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References

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