Ferrofluids, itinerant oscillator models

Stepanov and Shliomis [80] have proposed an egg model akin to a three-dimensional form of the itinerant oscillator model [72]. (We recall [72] that in the itinerant oscillator, one relaxation mechanism occurs due to rotation of the oscillator as a whole, the other due to jumping of the inner rotator over a potential barrier) whereby the interdependence of the two relaxation mechanisms is taken into account. In the egg model [80], the ferrofluid particle is represented as an egg of volume V (the hydrodynamic volume) embedded in the liquid with viscosity 17. The magnetic moment of the ferroparticle is modeled by the yolk of volume V magnetic torque acts directly on the yolk but due to the viscosity of the white it is also transmitted to the eggshell. Such a model allows one to take into account the coupling between the two mechanisms in a quantitative way so that its influence on and may be estimated. 

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