The disclination model of field induced transition between twisted and uniform structure in thin planar SmC* samples

Abstract

In thin unwound SmC* samples with SmC* layers perpendicular to the glass cover there is the twist of molecules along the sample thickness. Under the influence of an external electric field the transition between twisted and uniform structure occurs by the creation and growing of the uniform nuclei. A nucleus of uniform structure is bounded by a π-disclination loop. The model using the pair of line ±π-twist disclinations is used to describe the behaviour of this nucleus in external electric field. The estimation of electric field E ¹ _c leading to the growth of uniform structure in twisted one when field increases and the estimation of E ¹¹ _c for uniform-twisted transition in decreasing field are given.