Flexoelectric E ect in Biaxial Nematics
نویسنده
چکیده
The exoelectric e ect provides a linear coupling between electric polarization and orientational deformation in liquid crystals. It in uences many electrooptical phenomena and it is used in some bistable nematic devices. A statistical theory of dipole exoelectric polarization in biaxial nematic liquid crystals is used to calculate temperature dependence of order parameters, elastic constants, and exoelectric coe cients. The splitting of the two Meyer exoelectric coe cients and the appearance of new exoelectric coe cients is obtained at the uniaxial-biaxial nematic transition. The ordering of the split exoelectric coe cients corresponds to the ordering of the split elastic constants.
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