New Chiral Series with Large Tilt Angle in the Ferroelectric Smectic Phase

Inclusions in Smectic C Films as Modeled by Disclinations

“…Optical analysis of the texture has revealed a radial c-director anchoring at the surface separating S C * and N* phases and the presence of a (−1)-wedge disclination in the neighbourhood of the inclusion [1][2][3]. The N* droplet can be represented by a (+1)-wedge disclination of finite length equal to the droplet length in the direction perpendicular to smectic layers.…”

“…First, the contribution to interaction due to layer deformations will be discussed. In experiments [1][2][3][4] the N* inclusions nucleate at temperatures above the bulk S C *-N* transition in the film. Similar observations were done in S C films near S C -N transition [5,6] where also nematic inclusions nucleate at temperatures above the bulk S C -N transition.…”

“…The chain formation in these films was explained as the consequence of dipolar interaction of inclusions [1][2][3][4].…”

“…The (−1)-wedge disclination corresponds to the notion of hyperbolic defect discussed in the Refs. [1][2][3]. Segments of (±1)-disclinations cannot terminate in the bulk of the film, but they are connected to form a disclination loop.…”

Direct Measurement of Interaction Forces Between Islands on Freely Suspended Smectic C Films Using Multiple Optical Tweezers

“…The structure and mechanical and thermodynamical properties of films have been widely studied since they were discovered by Friedel in 1922 [1,2]. Investigations of topological defects and the selforganization of circular inclusions in smectic C (SmC) free-standing films are quite recent [3][4][5][6][7][8]. Pettey et al [3] derived an expression for the director field associated with islands containing topological defects by minimizing the Frank elastic free energy of a smectic C film in 2D, assuming fixed boundary conditions on a circular disk on the film representing the island, and showed that there is a hyperbolic −1 point defect at a distance R 2 from the center where R is the disk radius.…”