Effect of field cooling process and ion-beam bombardment on the exchange bias of NiCo/(Ni, Co)O bilayers

被引:11
作者
Li, X. [1 ]
Lin, K. -W. [2 ]
Liu, H. -Y. [2 ]
Wei, D. -H. [3 ]
Li, G. J. [1 ]
Pong, P. W. T. [1 ]
机构
[1] Univ Hong Kong, Dept Elect & Elect Engn, Hong Kong, Hong Kong, Peoples R China
[2] Natl Chung Hsing Univ, Dept Mat Sci & Engn, Taichung 402, Taiwan
[3] Natl Synchrotron Radiat Res Ctr, Hsinchu 300, Taiwan
关键词
Magnetic thin films; Exchange bias; Ion-beam bombardment; DEPENDENCE;
D O I
10.1016/j.tsf.2014.03.032
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
The research on exchange coupled ferromagnetic/antiferromagnetic (FM/AF) bilayers has been the foundation of spintronic applications such as hard disk reading heads and spin torque oscillators. In order to further explore the exchange bias behavior of NiCo/(Ni, Co)O bilayers, effect of field cooling process, magnetic angular dependence, and ion-beam bombardment was investigated. The difference in film composition resulted in remarkable distinction in crystalline structures and domain patterns. The exchange bias field (Hex) in the bilayer systems exhibited a strong angular dependence. The negative Hex after a field cooling process indicated that the polarity of Hex can be defined by aligning the magnetization orientation of the FM NiCo layer with the applied field. Moreover, enhanced exchange bias effect was observed in the NiCo/(Ni, Co) O bilayers that resulted from the surface of the (Ni, Co) O layers bombarded with different Ar+ ion-beam energies using End-Hall voltages from 0 V to 150 V. The interface spin structures as well as the surface domain patterns were altered by the ion-beam bombardment process. These results indicated that the exchange bias field of NiCo/(Ni, Co) O bilayer systems could be tailored by field cooling process, angular dependence of magnetic properties, and post ion-beam bombardment. (C) 2014 Elsevier B. V. All rights reserved.
引用
收藏
页码:383 / 389
页数:7
相关论文
共 33 条
[11]   Calculations of exchange bias in thin films with ferromagnetic/antiferromagnetic interfaces [J].
Koon, NC .
PHYSICAL REVIEW LETTERS, 1997, 78 (25) :4865-4868
[12]   Exchange bias effects of NiFe/NiO bilayers through ion-beam bombardment on the NiO surface [J].
Li, Guijun ;
Leung, Chi Wah ;
Shueh, Chin ;
Hsu, Hsun-Feng ;
Huang, Hsuan-Rong ;
Lin, Ko-Wei ;
Lai, Pui To ;
Pong, Philip W. T. .
SURFACE & COATINGS TECHNOLOGY, 2013, 228 :S437-S441
[13]   Positive exchange bias in a Ni80Fe20/NixFe1-xO thin-film bilayer [J].
Lin, K. -W ;
Tzeng, Y. -M ;
Guo, Z. -Y. ;
Liu, C-Y. ;
van Lierop, J. .
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 2006, 304 (01) :E124-E127
[14]  
Lin KW, 2007, J NANOSCI NANOTECHNO, V7, P265, DOI 10.1166/jnn.2007.022
[15]   Tailoring interfacial exchange coupling with low-energy ion beam bombardment: Tuning the interface roughness [J].
Lin, K. -W. ;
Mirza, M. ;
Shueh, C. ;
Huang, H. -R. ;
Hsu, H. -F. ;
van Lierop, J. .
APPLIED PHYSICS LETTERS, 2012, 100 (12)
[16]   Anomalous exchange bias behavior in ion-beam bombarded NiCo/(Ni,Co)O bilayers [J].
Lin, K. -W. ;
Guo, J. -Y. ;
Liu, H. -Y. ;
Ouyang, H. ;
Chan, Y. -L. ;
Wei, D. -H. ;
van Lierop, J. .
JOURNAL OF APPLIED PHYSICS, 2008, 103 (07)
[17]   Cooling Field and Ion-Beam Bombardment Effects on Exchange Bias Behavior in NiFe/(Ni,Fe)O Bilayers [J].
Lin, K. -W. ;
Wei, M. -R. ;
Guo, J. -Y. .
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY, 2009, 9 (03) :2023-2029
[18]  
Lin K.W., 2009, J APPL PHYS, V105
[19]   Structural and magnetic characterization of ion-beam deposited NiFe/NixFe1-xO composite films [J].
Lin, KW ;
Gambino, RJ ;
Lewis, LH .
JOURNAL OF APPLIED PHYSICS, 2003, 93 (10) :6590-6592
[20]   Interface domain wall and exchange bias phenomena in ferrimagnetic/ferrimagnetic bilayers [J].
Mangin, S ;
Montaigne, F ;
Schuhl, A .
PHYSICAL REVIEW B, 2003, 68 (14)