Yl. Raikher et Vi. Stepanov, DYNAMIC BIREFRINGENCE IN MAGNETIC FLUIDS - THE EFFECT OF MECHANICAL AND MAGNETIC DEGREES OF FREEDOM OF THE PARTICLES, Europhysics letters, 32(7), 1995, pp. 589-594
A new theoretical approach to the dynamic field-induced birefringence
in magnetic fluids is presented. On equal basis it takes into account
both internal (magnetic) and external (mechanical) orientation relaxat
ions of the particles. Besides uniting several former approximate mode
ls, already tested experimentally, it covers a variety of intermediate
cases which have been never addressed before.