Light-stimulated electro-optics by azo-doped aerosil/7CB nanocomposites

• Autorzy: Hadjichristov G. B. , Marinov Y. G. , Petrov A. G. , Prasad S. K.

Identyfikatory

DOI

10.1016/j.opelre.2018.04.001

• Języki publikacji: EN

Abstrakty

EN

Photoactive nanofilled nematic is proposed. Stable three-component photoresponsive nanocompositewas prepared from photo-insensitive nanofilled nematic by inclusion of 3 wt.% azobenzene-containingphotoactive mesogen 4-(4’-ethoxyphenylazo)phenyl hexanoate (EPH). The host nanofilled nematicwas produced from the room-temperature nematic liquid crystal 4-n-heptyl cyanobiphenyl (7CB) and3 wt.% filler of Aerosil 300 hydrophilic silica nanospheres of size 7 nm. Apparent effect of stimulation with a relatively weak continuous illumination by UV light (375 nm wavelength) takes placefor both the alternating-current electric field-dependent optical transmittance and the electro-opticamplitude-frequency modulation by thin films (25 μm thick) of the EPH/aerosil/7CB nanocomposite. Thelight-stimulated electro-optics of EPH-doped aerosil/7CB films and the corresponding reversible lightcontrol are achieved through trans-cis-trans photoisomerization of the photoactive agent EPH. As such,the initial electro-optical response of the studied photoactive nanocomposites is recovered with continuous blue-light illumination. The examined EPH/aerosil/7CB nanocomposites exhibit photo-controllableelectro-optical response that is of practical interest.

Słowa kluczowe

EN

azo-doped nematic nanocomposites; silica nanoparticles; optical films; electro-optical properties; photo-controllable electro-optics

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2018
• Tom: Vol. 26, No. 2
• Strony: 172--182
• Opis fizyczny: Bibliogr. 52 poz., rys., wykr.

Twórcy

autor

Hadjichristov G. B.

• Laboratory of Optics & Spectroscopy, Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., Sofia, BG-1784, Bulgaria

autor

Marinov Y. G.

• Laboratory of Biomolecular Layers, Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., Sofia, BG-1784, Bulgaria

autor

Petrov A. G.

• Laboratory of Biomolecular Layers, Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., Sofia, BG-1784, Bulgaria

autor

Prasad S. K.

• Centre for Nano and Soft Matter Sciences, P.O. Box 1329, Jalahalli, Bengaluru 560 013, India

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Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2018).