Optical transmittance of ferronematic materials in the visible range

摘要

A kind of ferronematic materials composed of 4-cyano-4'-pentylbiphenyl nematic liquid crystal and oil-based Fe_3O_4 magnetic fluid was prepared by using ultrasonic agitation. The influence of wavelength of incident light, concentration and thickness of samples and externally magnetic field strength on the transmittances of pure magnetic fluids and as-prepared ferronematic materials were obtained. The transmittances of pure magnetic fluids and ferronematic materials increase gradually with the incident wavelength and slightly with the magnetic field, but decreases with the volume fraction of magnetic particle and sample thickness at certain wavelength. For the ferronematic materials, their transmittances also increase with the volume fraction of nematic liquid crystal. The maximum relative enhancement in transmittance is achieved to be around 190% at the wavelength of 500 nm in our experiments.