Reduced power consumption in nickel zinc ferrite nanoparticles doped blue phase chiral nematic liquid crystal devices

Abstract

The effect of nickel zinc ferrite (NZFO (Ni0.5Zn0.5Fe2O4)) nanoparticles in reducing the threshold voltage of blue phase (BP) in chiral nematic liquid crystal (CNLC) was studied at room temperature. Due to low concentration selected for doping, the structure of CNLC and the temperature window of BP is maintained in entire LC range. The significant reduction in threshold voltage (5.5V) for Freedericksz transition is recorded for doped CNLC. Strong interaction between guest NZFO nanoparticles and host, aligns the CNLC molecule in an ordered structure to considerably enhance dielectric permittivity and anisotropy of CNLC doped with 0.05wt% NZFO nanoparticles to reduce threshold voltage. The presence of NZFO nanoparticles reduces the impurity ions and associated free energy in CNLC, which lead to the observed decrease in dielectric loss and elastic constant, respectively, to contribute towards reduction in driving power (by ~50%) of BP based displays. The improved photoluminescence intensity of CNLC, in the presence of NZFO, promises as a potential material for optoelectronic devices.