Granular effects, magnetic

The copper bronze was supplied by BDH Chemicals Ltd. (Poole, England) as an extremely fine powder. The use of more granular electrolytic copper had no effect on the yield, but made magnetically operated stirring more difficult. 

The discussion of Eq. (21) is still correct even for magnetic granular metals, where the Hall effect has the anomalous nature [81], and its behavior at v a c is similar to that in bulk ferromagnetic metals. The only distinction is related to the difference between volumes of a sample and a cluster. 

Basic equations of the homogenization theory are applicable not only for scalar values of the constiments dielectric constants e, but also for the tensorial quantities. Indeed, evaluation of these equations does not demand any special requirements regarding the character of the electric displacement D and electric intensity E relation D = eeoE in which dielectric constant e can be tensorial. This fact enables us to calculate the effective dielectric constant Ceff for the composites with anisotropic constituents. It can be, for example, polymer composites with magnetic granular, the permittivity of which is tensorial quantity. The explicit form of the e tensor for magnetic media will be given in the next section. 

FIGURE 1 Change of the normalized electrical resistance (GMR effect) as a function of the magnetic field for a granular thin film of silver/cobalt prepared by molecular beam epitaxy. SOURCE Alof, 2000. 

Timopheev, A.A., Ryabchenko, S.M., Kalita, V.M., Lozenko, A.F., Trotsenko, P.A., Grishin, A.M., Munakata, M. Effect of interaction in the magnetization reversal relaxation of superparamagnetic granular CoFeB-Si02 films. Solid State Phenom. 152-153, 213-216... 

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