TY - JOUR
T1 - Thickness effect on the easy axis distribution in exchange biased Co/IrMn bilayers
AU - Tarazona, H. S.
AU - Tafur, M.
AU - Quispe-Marcatoma, J.
AU - Landauro, C. V.
AU - Baggio-Saitovitch, E.
AU - Schmool, D. S.
N1 - Publisher Copyright:
© 2019
Copyright:
Copyright 2019 Elsevier B.V., All rights reserved.
PY - 2019/8/15
Y1 - 2019/8/15
N2 - It is commonly assumed that in uncompensated FM/AF interfaces, the easy axes of antiferromagnetic grains are aligned toward the magnetic field direction applied during the film growth. However, due to several intrinsic and extrinsic factors, these easy axes can be aligned away from the unidirectional axis. In this context, the aim of this work is to study the relationship between the easy axes distribution (EAD) and thickness of both the ferromagnetic (FM) and antiferromagnetic (AF) layers in Co/IrMn bilayer systems. A phenomenological model for the free energy of the system that takes into account a domain wall formation in the AF layer and a Gaussian-type distribution of their easy axes is used. Thus, we simulate and fit the magnetization curves and get several magnetic parameters like rotatable anisotropy field, exchange bias field, coercivity and magnetic anisotropy. Our results show that when the AF thickness is increased, the width of the easy-axis distribution also increases following a power-law relationship. However, no correlation is observed when the FM thickness is varied. Furthermore, considering an easy-axis distribution we observe a significant reduction in coercivity as well as a slight decrease of the exchange bias field.
AB - It is commonly assumed that in uncompensated FM/AF interfaces, the easy axes of antiferromagnetic grains are aligned toward the magnetic field direction applied during the film growth. However, due to several intrinsic and extrinsic factors, these easy axes can be aligned away from the unidirectional axis. In this context, the aim of this work is to study the relationship between the easy axes distribution (EAD) and thickness of both the ferromagnetic (FM) and antiferromagnetic (AF) layers in Co/IrMn bilayer systems. A phenomenological model for the free energy of the system that takes into account a domain wall formation in the AF layer and a Gaussian-type distribution of their easy axes is used. Thus, we simulate and fit the magnetization curves and get several magnetic parameters like rotatable anisotropy field, exchange bias field, coercivity and magnetic anisotropy. Our results show that when the AF thickness is increased, the width of the easy-axis distribution also increases following a power-law relationship. However, no correlation is observed when the FM thickness is varied. Furthermore, considering an easy-axis distribution we observe a significant reduction in coercivity as well as a slight decrease of the exchange bias field.
KW - Easy axis distribution
KW - Exchange bias
KW - Rotatable anisotropy
UR - http://www.scopus.com/inward/record.url?scp=85065698888&partnerID=8YFLogxK
U2 - 10.1016/j.physb.2019.05.005
DO - 10.1016/j.physb.2019.05.005
M3 - Artículo
AN - SCOPUS:85065698888
SN - 0921-4526
VL - 567
SP - 11
EP - 16
JO - Physica B: Condensed Matter
JF - Physica B: Condensed Matter
ER -