Magnetic anisotropy random

One theory which has been successfully applied to the magnetic properties of R-compound alloys containing non-S-state R-ions is the theory of random magnetic anisotropy (RMA) of Harris et al. (1973). This has been used to calculate the magnetoresistivity of amorphous alloys exhibiting RMA. Bhat-tacharjee and Coqblin (1979) first obtained the static spin-spin correlation function of the RMA model by using a self-consistent two-spin cluster approximation. The quasi-elastic approximation of de Gennes and Friedel is then... 

It is not straightforward to examine the effect of the local magnetocrystalline anisotropy K on the averaged random magnetocrystalline anisotropy in experiment. This is because alteration of K requires a modification of chemical compositions which concurrently alters other influential parameters. Such concurrent alterations overshadow the effect of K on in experiment. This has made an explicit discussion on the scaling property of K in soft magnetic nanostructures challenging. 

Molecules that possess magnetic anisotropy experience a slight tendency toward alignment with an imposed magnetic field, but in normal isotropic solvents random thermal motions dominate, and no effects of orientation are usually... 

In these sperimagnetic structures, the subnetwork magnetisations are reduced. The influence of the exchange interactions and a random axial anisotropy on the average magnetic moment can be described using the Hamiltonian (Harris et al. 1973)... 

In an amorphous alloy the random atomic topology introduces fluctuations in both the magnetic exchange and anisotropy interactions, the latter coming from the random symmetry of the crystal field. These random magnetic interactions can be modelled as distributions in magnitude (exchange) or distributions in space (anisotropy) as follows... 

One of the arguments frequently offered by the proponents of zf techniques for magnetic studies of triplet states is that one can dispense with the troublesome mixed-crystal requirement. That is, even for randomly oriented molecules, the total spectral width should be small because of the absence of magnetic anisotropies in zf. In fact, this expectation is rarely fulfilled. 

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