Reversible Reflection Color-Control in Smectic Liquid Crystal Switched by Photo-Isomerization of Azobenzene



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Through the looking glass: A reflection color transition is demonstrated in a smectic liquid crystal doped with a photochromic azobenzene and a chiral agent with high helical twisting power. The reflection color can be switched reversibly due to the isomerization of azobenzene upon UV/visible irradiation (see picture).