Antiferromagnetic layer thickness dependence of the coercivity of the ferromagnetic/antiferromagnetic two-phase system

2013 ◽  
Vol 250 (10) ◽  
pp. 2153-2157 ◽  
Author(s):  
Zi-Zheng Guo ◽  
Wan-Jie Xiong
2001 ◽  
Vol 34 (14) ◽  
pp. 2085-2088 ◽  
Author(s):  
Zhi Hong Li ◽  
Yan Jun Gong ◽  
Min Pu ◽  
Dong Wu ◽  
Yu Han Sun ◽  
...  

1996 ◽  
Vol 79 (8) ◽  
pp. 5103 ◽  
Author(s):  
P. J. van der Zaag ◽  
A. R. Ball ◽  
L. F. Feiner ◽  
R. M. Wolf ◽  
P. A. A. van der Heijden

2010 ◽  
Vol 81 (22) ◽  
Author(s):  
Hyeok-Cheol Choi ◽  
Chun-Yeol You ◽  
Ki-Yeon Kim ◽  
Jeong-Soo Lee ◽  
Je-Ho Shim ◽  
...  

1991 ◽  
Vol 231 ◽  
Author(s):  
E. Tsang ◽  
J. C. Cates ◽  
M. Tan ◽  
A. Waknis ◽  
C. Alexander ◽  
...  

AbstractMagnetic properties of sputtered Ni/Al multilayers have been investigated by vibrating sample magnetometry and ferromagnetic resonance. In these compositionally modulated films (CMFs) the Al ‘spacer’ layer thickness was fixed at 3.5 nm while the total Ni content of each film was held constant at 308 nm. The thickness of the individual Ni layers was varied from 4.8 to 154 nm. The CMFs showed a variety of magnetic characteristics which were dependent on the thickness of the Ni layers. CMFs with Ni layer thickness 30 nm and above showed clear evidence of perpendicular anisotropy. This anisotropy is characterized by low-remanence perpendicular hysteresis loops of the type commonly found in CoCr alloy films. As the Ni layer thickness diminishes the perpendicular anisotropy decreases and is eventually lost. Simultaneously, the CMFs show increasing in-plane remanence, rising to a peak squareness of greater than 0.5 at a Ni layer thickness of 11 nm. As the Ni thickness continues to decrease, the remanence again declines. At Ni thicknesses of a few nm the CMFs become quasi-superparamagnetic. These CMFs do not show a monotonic reduction in saturation magnetization, Ms, with decreasing Ni layer thickness. Instead, both Ms and the coercivity, Hc, pass through a maximum in the region of 40–80 nm Ni layer thickness. FMR measurements were also made on these films. A plot of the effective anisotropy field produces data of a similar form to the Ms versus Ni layer thickness plot, again with a clear maximum. The FMR data also reveals interesting resonances in the films exhibiting perpendicular anisotropy. The presence of satellite resonances adjacent to the principal resonance peaks seems to suggest, in structural terms, a two-phase system as the basis of the observed anisotropy.


2011 ◽  
Vol 675-677 ◽  
pp. 1263-1266
Author(s):  
Jian Wang ◽  
Shinji Muraishi ◽  
Ji Shi ◽  
Yoshio Nakamura

We have used ferromagnet/antiferromagnet/ferromagnet sandwich structure to probe the antiferromagnetic layer thickness dependence of exchange bias in sputter-deposited Co/CoO/Co trilayer. The exchange coupling occurring at the upper ferromagnetic/antiferromagnetic interface is always found to be stronger than the one at the lower antiferromagnetic/ferromagnetic interface. The grain growth with increasing antiferromagnetic layer thickness can lead to a gradient of grain size distribution through the whole antiferromagnetic layer. Consequently, the relatively large grains at the upper interface would results in a rougher interface which we treat as structural defects and can significantly enhance exchange bias through domain state model. The slightly decrease of exchange coupling with increasing antiferromgnetic layer thickness indicates that the exchange bias is only governed by the grains that are thermally stable but whose anisotropy energy is low enough to be set.


2003 ◽  
Vol 68 (21) ◽  
Author(s):  
M. Ali ◽  
C. H. Marrows ◽  
M. Al-Jawad ◽  
B. J. Hickey ◽  
A. Misra ◽  
...  

1991 ◽  
Vol 24 (7) ◽  
pp. 59-64 ◽  
Author(s):  
R. W. Szetela

Steady-state models are presented to describe the wastewater treatment process in two activated sludge systems. One of these makes use of a single complete-mix reactor; the other one involves two complete-mix reactors arranged in series. The in-series system is equivalent to what is known as the “two-phase” activated sludge, a concept which is now being launched throughout Poland in conjunction with the PROMLECZ technology under implementation. Analysis of the mathematical models has revealed the following: (1) treatment efficiency, excess sludge production, energy consumption, and the degree of sludge stabilization are identical in the two systems; (2) there exists a technological equivalence of “two-phase” sludge with “single-phase” sludge; (3) the “two-phase” system has no technological advantage over the “single-phase” system.


1985 ◽  
Vol 50 (8) ◽  
pp. 1642-1647 ◽  
Author(s):  
Štefan Baláž ◽  
Anton Kuchár ◽  
Ernest Šturdík ◽  
Michal Rosenberg ◽  
Ladislav Štibrányi ◽  
...  

The distribution kinetics of 35 2-furylethylene derivatives in two-phase system 1-octanol-water was investigated. The transport rate parameters in direction water-1-octanol (l1) and backwards (l2) are partition coefficient P = l1/l2 dependent according to equations l1 = logP - log(βP + 1) + const., l2 = -log(βP + 1) + const., const. = -5.600, β = 0.261. Importance of this finding for assesment of distribution of compounds under investigation in biosystems and also the suitability of the presented method for determination of partition coefficients are discussed.


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