Curvature oscillations and linear electro-optical effect in a surface layer of a nematic liquid crystal
نویسندگان
چکیده
Damped curvature oscillations are excited at the surface between a nematic liquid crystal and a solid substrate, from the linear coupling of an AC electric field with the flexoelectric properties of the medium. The waves are detected by a modulation ellipsometry technique. Linear-in-field oscillations of the director in the surface nematic layer have been observed. The amplitude and characteristic response time of the oscillations are defined by visco-elastic and flexoelectric properties of the medium and the overlaping of the curvature wave with the profile of the sampling optical evanescent wave. A simple model is discussed which is in good
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