Neel-Brown process

In sufficiently small ferro- or ferrimagnetic particles with an effective uniaxial anisotropy per unit volume Ka the relaxation of the magnetization will vary exponentially with the temperature following a Neel-Brown process characterized by a relaxation time given by... 

We reiterate that the analysis given above (quite apart from the question of identification of the largest relaxation time of Brown s equation with that of the magnetization, in the Neel limit, a justification for which is provided by the numerical calculations presented in [17]), makes the assumption that the Debye and Neel processes may be treated independently. 

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