Effective optical nonlinearities of glass-forming ionic liquid crystals containing metal and carbon nano-dopants

Liquid crystals are known for their tunable physical properties, which have revolutionized information technology and deepened our understanding of soft matter materials. A less explored subfield of liquid crystal science and technology includes liquid crystal glasses stable at room temperature. In this presentation, we discuss the structure, optical, and nonlinear-optical properties of glass-forming ionic liquid crystals made of cadmium octanoate containing metal (gold or silver), carbon, and both metal and carbon nano-dopants. The vitrified liquid crystal state of cadmium octanoate resembles a smectic-A structure that can be exploited as an anisotropic host for nano-dopants with a strong nonlinear-optical response. Z-scan measurements of the studied mesomorphic glass nanocomposites revealed several nonlinear-optical mechanisms, leading to the intensity dependence of the effective nonlinear-absorption coefficients and nonlinear-refractive indices of such unconventional materials. The simultaneous use of both gold and carbon nano-dopants dispersed in a liquid crystal glass leads to substantial modifications of the nonlinear-optical response, including a change in the sign of the effective nonlinear absorption coefficient.