Collinear mirage effect measurement of the thermal diffusivity in Ferronematics

Thermal diffusivity results obtained for a lyotropic nematic liquid crystal sample doped with different amounts of ferrofluid (ferronematics) are reported. The collinear mirage technique was used for measurements along axes parallel and perpendicular to the director of this anisotropic material. The results show that as the ferrofluid concentration increases the thermal diffusivity decreases, leading to values even lower than those already reported for plain lyotropic nematic liquid crystals. The ratio of the two diffusivities increases as the ferrofluid concentration increases, reaching the exact value theoretically expected, though not achieved experimentally, for plain lyotropic nematic liquid crystals.