Photo-controllable electro-optics of aerosil/7CB nanocomposite nematic doped with azo-bonded molecules

INERA Conference 2015: Light in Nanoscience and Nanotechnology

Marinov, Y.G.^1 ; Hadjichristov, G.B.^1 ; Petrov, A.G.^1 ; Prasad, S Krishna^2

Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, Tzarigradsko chaussee, Sofia

1784, Bulgaria^1

Centre for Nano and Soft Matter Sciences, Jalahalli, Bangalore

560 013, India^2

关键词: Alternating current;    Amplitude frequency;    Azobenzene molecules;    Bonded molecule;    Electro-optic applications;    Electro-optic modulation;    Nano-structured;    Photo-responsive;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/682/1/012030/pdf
DOI  :  10.1088/1742-6596/682/1/012030

来源: IOP

【 摘 要 】

We demonstrate that the electro-optics of nanostructured nematic liquid crystal (LC) doped with a small amount of photoactive LC molecules can be efficiently controlled by light. In particular, the inclusion of 3 wt.% azobenzene LC 4-(4'-ethoxyphenylazo)phenyl hexanoate (EPH) into a gel nanocomposite material produced from nematic LC heptylcyanobiphenyl (7CB) and 3 wt.% hydrophilic silica nanoparticles of size ca. 7 nm (Aerosil 300) allows both the static (the transmittance versus the voltage) and the dynamic (amplitude-frequency electrooptic modulation) characteristics of thin films (25 μm) of such a complex LC system in an alternating-current electric field to be enhanced by UV light at a wavelength of 375 nm. This photo-effect that is reversed with white light is based on the photo-isomerization of the doped azobenzene molecules. The efficient photo control makes the considered EPH-doped Aerosil/7CB photo-responsive nematic nanocomposites attractive for specific electro-optic applications.