Structured media based on magnetic colloids as a promising material for magnetically controllable optical elements

Abstract

The magneto-optic effects in magnetic emulsions with low interfacial tension based on aviation hydraulic oil and in magnetic colloids with an extensive system of nanoparticle aggregates is investigated. The effect of changing the transparency in a longitudinal magnetic field is detected, the magnitude of which can be controlled by changing the strength and orientation of the magnetic field. In a transverse field, the effect of anisotropic diffractive scattering of light by irregular and regular systems of microdroplets elongated along the field is demonstrated. Diffraction patterns are obtained that can be configured by adjusting the ratio of components of a rotating magnetic field. It is concluded that magnetic emulsions and magnetic colloids with concentrated nanoparticle aggregates are promising as materials for magnetically controllable optical elements