Abstract
Temperature dependence of the field hysteresis loop (δU) of the cholesterol-nematic phase transitions in mixtures based on strong and weak polar nematics. The ephires of the cholesterol (0.2… 1.6 weight %) were used as optically active dopants. For mixtures, in which fluctuation embryos have a major role at low temperatures, anomalous growth of δU is observed. The influence of temperature dependence of constants of elasticity and step of induced spiral on analogical dependence δU =f(T) takes place. Magnitude of δU can be changed by changing the percentage of cholesterine in the mixture.