Polarization Frederiks-Transition in SmC∗ Liquid Crystal Films
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چکیده
A new Frederiks-transition is predicted for freely suspended SmC∗-liquid crystal films. Frederiks transitions in nematic liquid crystals are the result of the competition between two orientational effects. One coming from the orientation of the director field at the boundary and one from the orientational effect due to an external electrical or magnetic field acting on the bulk orientation of the director field via the magnetic or dielectric susceptibility anisotropy. Here we discuss the consequences of the additional ferroelectric torques. A new branch for the splay Frederiks transition due to the presence of the spontaneous polarization in SmC∗liquid crystal films is predicted, and it is pointed out that on this new branch a transition from supercritical to subcritical bifurcation behavior can occur. PACS numbers: 47.20, 61.30
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تاریخ انتشار 1997