Polar Smectic Films
نویسندگان
چکیده
We report on a new experimental procedure for forming and studying polar smectic liquid-crystal films. A free-standing smectic film is put in contact with a liquid drop, so that the film has one liquid-crystal/air interface and one liquid-crystal/liquid interface. This polar environment results in changes in the orientational order parameter textures observed in the film, including a boojum texture and a previously unobserved spiral texture in which the winding direction of the spiral reverses at a finite radius from its center. Some aspects of these textures are explained by the presence of a Ksb term in the bulk elastic free energy that favors a combination of splay and bend curvatures. [S0031-9007(99)09072-9]
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تاریخ انتشار 1999