Study of magneto-optical effects in a damping-oil-based magnetic fluid in the infrared region

The influence of long range interparticle correlations on the magnetically induced optical anisotropy in magnetic colloids

“…(14) and (15), together with the analytically expressed equations (10)- (12) which explicate the pair correlation function g 2 (1, 2) and Eq. (8) which explicates h 12 (ψ), give the quantitative dependence of the complex dielectric constant on the polarization angle ψ, the intensity of the external magnetic field (H), the magnetic nanoparticles concentration (Φ) and diameter (D), and the sample temperature (T ).…”

“…Kopcansky and co-workers [12] showed that the absorption of light polarized at θ c is independent of the magnetic field intensity in magnetic colloids where the rotation mechanism is responsible for the magnetically induced optical anisotropy. On the other hand, we found experimental evidence that the absorption coefficient of light polarized at θ c is diminishing with increasing both magnetic field intensity and sample particle volume fraction in an ultra-stable magnetic colloid with magnetite particles stabilized with oleic acid and dispersed in transformer oil (details on the experiment and the results will be published elsewhere).…”

Magneto-Optical Effects in Thin Layer Magnetic Fluids and in Films Obtained After Base Liquid Evaporation

“…where: all and al.' are diagonal elements of the polarizability tensor for a single particle or aggregate respectively [2] , a= ~HJkBT, ~ is the magnetic moment…”

“…The optical transmissivity of the magnetic fluid film has been investigated by Kopcansky et al [I] in the infrared range. The absorbtion of light in the transverse geometry as a function of the applied magnetic field intensity was presented in [2]. Particularly, the effects of particle interaction on magneto-optical birefringence in magnetic fluids have been studied by Sakhnini and Popplewell [3,4] and by Gerligand et al [5].…”

“…The discusions of the results was based on the formula:T(S,H,k) = T(S,H= O,k)cxp! -Ll A (S,H,k) dlof magnetic particles <P, as a function of the intensity R'of the magnetic field where it is settled, is given by the(2) formula: where Ll A (S,H,k) = A (S,H,k) -A (S,H=(I,i<) for values S = 0 and S = 1tJ2 of the angle between the electric field intensity Eror the light used and the external magnetic field intensity Ft.The wavenumber of the laser beam used in our experiments was k= 15R02 cm-I.The second series of samples were obtained from the same magnetic fluid after the base liquid evaporation. The magnetic Iluid cell. )…”