By Topic

Temperature dependence of magnetic anisotropy of Ga-substituted cobalt ferrite

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $31
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

7 Author(s)
Ranvah, N. ; Wolfson Centre for Magnetics, Cardiff University, Cardiff CF24 3AA, United Kingdom ; Melikhov, Y. ; Jiles, D.C. ; Snyder, J.E.
more authors

Your organization might have access to this article on the publisher's site. To check, click on this link:http://dx.doi.org/+10.1063/1.2832503 

The temperature dependence of magnetization, magnetic anisotropy, and coercive field of gallium-substituted cobalt ferrite was investigated for a series of compositions of CoGaxFe2-xO4 (0≤x≤0.8). Hysteresis loops were measured for each sample over the range of -5 T≤μ0H≤5 T for selected temperatures between 10 and 400 K. The magnetization at 5 T and low temperatures was found to increase for the lower Ga contents (x=0.2 and 0.4) compared to pure CoFe2O4, indicating that at least initially, Ga3+ substitutes predominantly into the tetrahedral sites of the spinel structure. The high field regions of these loops were modeled using the law of approach to saturation, which represents the rotational process, together with an additional linear forced magnetization term. The first order cubic magnetocrystalline anisotropy coefficient K1 was calculated from curve fitting to these data. It was found that K1 decreased with increasing Ga content at all temperatures. Both anisotropy and coercivity increased substantially as temperature decreased. Below 150 K, for certain compositions (x=0, 0.2, 0.4), the maximum applied field of μ0H=5 T was less than the anisotropy field and, therefore, insufficient to saturate the magnetization. In these cases, the use of the law of approach method can lead to calculated values of K1<- /inf> which are lower than the correct value.

Published in:

Journal of Applied Physics  (Volume:103 ,  Issue: 7 )