Numerical study of deformations induced by ac electric field in insulating flexoelectric nematic layers

• Autorzy: Derfel G. , Buczkowska M.
• Języki publikacji: EN

Abstrakty

EN

The influence of the frequency f of applied ac electric field on the time dependence of electric field induced deformations of homeotropic nematic layers is studied numerically. Three kinds of nematic liquid crystals were considered: – non-flexoelectric nematic with negative dielectric anisotropy, ∆ɛ < 0 – dielectrically compensated nematic (∆ɛ = 0) possessing flexoelectric properties determined by the positive sum of flexoelectric coefficients e = e₁₁ + e₃₃ > 0 – nematic characterised by both ∆ɛ < 0 and e > 0. It was found that at sufficiently low frequencies, the deformations varied with time. The deformations of purely dielectric nature had the period 1/(2f). When the frequency was increased, a stationary director distribution was achieved, determined by the rms value of the ac voltage. The time period of purely flexoelectric distortions was equal to 1/f. There was a well defined cut-off frequency above which these deformations vanished. In the case of dielectrically anisotropic and flexoelectric nematic, the flexoelectric contribution vanished above a critical frequency and the deformation of dielectric nature stabilized at high frequencies.

Słowa kluczowe

EN

flexoelectric nematic; ac electric field induced deformations

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2011
• Tom: Vol. 19, No. 1
• Strony: 66--70
• Opis fizyczny: Bibliogr. 14 poz., wykr.

Twórcy

autor

Derfel G.

• Institute of Physics, Technical University of Łódź, 219 Wólczańska Str., 90-924 Łódź, Poland

autor

Buczkowska M.

• Institute of Physics, Technical University of Łódź, 219 Wólczańska Str., 90-924 Łódź, Poland

Bibliografia

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