Coordinated chain motion resulting in intensity variation of light transmitted through ferrofluid film

Abstract

While a suitable magnetic field is applied to a ferrofluids film, magnetic nanoparticles in the film would form chain-like structure. Because of the action of magnetic convergent force (MCF) and magnetic divergent force (MDF), the chains will move coordinately towards to the axis of the field, then do apart from the center. From geometric shadowing effect, variation in the intensity of light transmitted through ferrofluids film is in relation to the coordinate motion of the chains. And a radiate synchromotion of the chain groups is constructed equivalently for describing the relation between transmitted light's intensity varying and chains moving. From the motion equation of one chain group, the relation is illustrated qualitatively by computer simulation. The experimental results show that the field-induced variation of light transmitted through ferrofluids film is a nonlinear relaxation process with intrinsic noise, and are in agreement with the behavior simulated by using the model of coordinated chains motion (MCCM).