Numerical investigation of influence of ionic space charge and flexoelectric polarization on measurements of elastic constants in nematic liquid crystals

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

Abstrakty

EN

Deformations of nematic layers caused by magnetic field allow determination of the elastic constants of liquid crystal. In this paper, we simulated numerically the deformations of planar and homeotropic nematic layers. The flexoelectric properties of the nematic and presence of ions were taken into account. Our aim was to show the influence of flexoelectricity on the results of the real measurement of the elastic constants k₃₃ and k₁₁. In these simulations, we calculated the optical phase difference Δ Φ between the ordinary and extraordinary rays of light passing through the layer placed between crossed polarizers as a function of the magnetic field induction B. One of the elastic constants can be calculated from the magnetic field threshold for deformation. The ratio k₃₃/k₁₁ can be found by means of fitting theoretical ΔΦ(B) dependence to the experimental results. The calculations reveal that the flexoelectric properties influence the deformations induced by the external magnetic field. In the case of highly pure samples, this may lead to false results of measurement of the elastic constants ratio k₃₃/k₁₁

Słowa kluczowe

EN

nematic liquid crystal; magnetic field induced deformations; elastic constants; flexoelectric polarization; ionic space charge

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2009
• Tom: Vol. 17, No. 2
• Strony: 95--98
• Opis fizyczny: Bibliogr. 13 poz., wykr.

Twórcy

autor

Buczkowska M.

autor

Derfel G.

autor

Konowalski M.

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

Bibliografia

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