Enhanced electro-optical nonlinear responses of doped nematic liquid crystals: Towards optoelectronic devices

•Chiral dopants modify physical properties of a nematic liquid crystal.•Iregular nonlinear optical behaviors were observed by doping chiral dopants.•High polarizability and Kerr constant were obtained for 4% of chiral dopants. Liquid crystals with high electro-optical responses play significant roles in optics and photonics. Providing a simple method for increasing the electro-optical behaviors of liquid crystals can be considered one of the most important and challenging research areas. In this work, left-handed chiral dopants and temperature effects on the electro-optical properties of pure and doped nematic liquid crystals with different percentages of chiral dopants were investigated. Despite decreasing the Kerr constant by increasing the percentage of chiral dopants, and temperature, the maximum values were observed for 4% of chiral dopants near the transition temperature. In this case, the value of Kerr constant is approximately 20 times that of a pure liquid crystal sample. This interesting result can be related to the changes in molecular polarizability due to molecular interactions. Hence, doped liquid crystals with high and controllable responses can be a good candidate for designing optoelectronic devices.