Functional Doping of a Liquid Crystal Matrix for Photocontrolled Ordering of Nanocomposites

The phase behavior of a liquid-crystal (LC) matrix incorporated by new azo-chromophore compounds that undergo conformational changes under irradiation by light with wavelengths of 365 and 450 nm has been studied. The illumination conditions optimum for controlling the transition from the isotropic to LC phase have been established together with the time required for the UV-induced LC transition to the isotropic phase and the time for which a medium retains its isotropic liquid properties after UV illumination. The feasibility of controlling the localization of CdSe/ZnS quantum dots incorporated into the matrix with azo-chromophore has been demonstrated. A dynamic experiment with displacement of the sample relative to a slit mask has shown the possibility of moving quantum dots along with the isotropic melt front; the temperature optimum for this effect has been determined.