Photoinduced Isotropic State of Cholesteric Liquid Crystals: Novel Dynamic Photonic Materials


  • This work was supported by US AFOSR STTR and US AF SBIR programs.


The photoinduced isotropic (PHI) state of cholesteric liquid crystals (CLCs) induced by the UV irradiation of a highly doped (azobenzene liquid crystal) CLC can be stable for tens of hours dominated by the lifetime of the cis isomers. Low-power laser light can be used to write complex 2D images (a car is shown), where the contrast arises from restoration of the reflective cholesteric phase.

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