Synchrotron X-ray Microbeam Characterization of Smectic a Liquid Crystals under Electric Field
نویسندگان
چکیده
When an electric field is applied to chiral smectic A (SmA) liquid crystals, a tilt is induced in the director of orthogonal SmA liquid crystals (electroclinic effect). The layer shrinkage due to the tilted smectic arrangement is mitigated by local layer deformation. This paper presents detailed measurements of the local layer spacing under the electroclinic effect of the chiral SmA phase in a surface-stabilized liquid crystal cell, performed using time-resolved synchrotron X-ray microbeam diffraction with a high-resolution CCD X-ray detector. It is shown that the layer spacing variation corresponds well to the applied electric field and the horizontal chevron angle. Further, techniques for the simultaneous measurement of layer deflection and molecular orientation are discussed.
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