Accuracy of 45° torque method for obtaining anisotropy constant of 2D random films

Coll. of Eng., Nihon Univ., Fukushima
IEEE Transactions on Magnetics (Impact Factor: 1.39). 10/1999; 35(5):2673 - 2675. DOI: 10.1109/20.800944
Source: IEEE Xplore


Computer simulation was used to examine the accuracy of anisotropy
energy constant, K2 of thin film media obtained from the
45° torque method. The easy axes of the media were distributed
randomly in plane. The obtained Ku value depends on range of
the applied field. For 2D random media with HK=1-40 kOe, M
s=100-600 emu/cm3, A=0-1×10-6
erg/cm, separation between adjacent grains=0-a nm, the difference
between obtained Ku value and exact Ku was at most
20%, if the range of applied field was larger than 10-20 kOe. Here, the
standard values of the physical parameters were HK=10 kOe, M
s=460 emu/cma, A=0, separation between adjacent grains=0, and
each parameter was varied successively

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