A.G. Petrov¹, I.G. Marinov¹, G.B. Hadjichristov¹, S. Sridevi², U.S. Hiremath², C.V. Yelamaggad², S.K. Prasad^2
1Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia, Bulgaria
²Centre for Soft Matter Research, Jalahalli, Bangalore 560 013, India

Abstract. Photosensitive soft matter based upon guest-host liquid crystal systems was prepared by mixing azobenzene-containing mesogens with the nematic liquid crystal 4-butyl-cyclohexane carboxylic acid 4-pentyloxy-phenyl ester (CM80). Binary mixtures of the host CM80 with three azo-bonded compounds as UV-active dopants (guests) at a relatively small concentration of 1~wt.% were characterized by thermo-optical, dielectric, spectral and flexoelectric measurements. The study aimed to determine the mechanisms that result in variations of material parameters caused by light-driven molecular conformation change of the azo-dye guest molecules (the transition from rod-shaped trans isomers to bent-shaped cis isomers).

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