Effect of temperature on memory effect in nematic phase of liquid crystal and their composites with aerosil and geothite nanoparticles
Katarína Zakuťanská, Dmytro Miakota, Veronika Lacková, Shie‐Chang Jeng, Dorota Węgłowska, Filippo Agresti, Markéta Jarošová, Peter Kopčanský, Natália Tomašovičová
Abstract
Liquid crystal doped with aerosil nanoparticles is known for exhibiting an electromechanical memory effect. After exposing the composite to the electric field the state induced by the electric field stays remembered due to the presence of aerosil nanoparticles. In this paper, we investigated the memory effect induced by electric and magnetic fields. Liquid crystal 4-cyano-4′-pentylbiphenyl doped with non-magnetic aerosil nanoparticles and a mixture of aerosil nanoparticles and elongated magnetic goethite nanoparticles were explored via capacitance measurements. Studied systems exhibited hysteresis in capacitance-voltage and capacitance-magnetic field dependences. The measurements revealed a great impact of temperature and heating/cooling rate on the hysteresis of the system. Observed electromechanical and magnetomechanical memory effect provides potential use of the system as voltage-driven or magnetic field-driven non-volatile memory devices.