Frequency modulation response of a liquid-crystal electro-optic device doped with nanoparticles

Palladium nanoparticles covered with liquid-crystal molecules were prepared by UV irradiation of an alcohol solution of palladium(II) acetate in the presence of liquid-crystal molecules. The prepared Pd nanoparticles have an average diameter of 2.5 nm. A twisted nematic (TN) liquid-crystal device (LCD) was fabricated by doping with Pd nanoparticles covered with another kind of nematic liquid-crystal molecules. In this device the sign of the dielectric anisotropy (Deltaepsilon) of the liquid-crystal molecules, which cover Pd nanoparticles, is opposite to that of nematic liquid-crystal molecules, which work as the host of the device (Deltaepsilon>0). The TN-LCD cell fabricated in this research exhibits a frequency modulation response to an applied alternative voltage wave form. (C) 2002 American Institute of Physics.