Experimental investigation of the magnetic properties of a liquid crystal MBBA and ferromagnetic suspensions based on it
This article shows the measured dependences of the Frederiksz threshold field for liquid crystal (LCD) MBBA and ferromagnetic suspension (FN) based on it. Magnetite particles (Fe3O4) were used as magnetic particles, the volume fraction of which was f = 4T0"<sup>4</sup>. Electron microscopy showed that magnetite particles have a quasispherical shape. The particle size distribution is constructed. The average particle diameter was 10 nm. A technique for preparing samples for doping a nematic matrix with ferromagnetic particles and a liquid crystal cell device are described. Dielectric measurements are performed on a precision RLC WK 6505B analyzer in a constant magnetic field with induction from 0 to 0.6 T. It is shown that the Frederiksz threshold field for the FN is significantly smaller than for the nematic matrix. Temperature dependences of the Frederiksz threshold field are constructed. It is shown that with a temperature rise the threshold field values decrease