2A09 An important role played by Casimir type fluctuation force due to discrete flexoelectric polarization in stabilizing two kinds of staircases in chiral tilted fluid smectics

Abstract

Conventional dispersion and steric interactions between mesogenic molecules generally promote SmC^*, while interlayer orientational correlations between transverse molecular dipoles stabilize anticlinic SmC_A^*. Ferroelectric and antiferroelectric orders thus produced are frustrated because of the XY freedom and the low-energy barrier between them. The Casimir type long-range interactions due to the polarization fluctuations can naturally explain not only a series of subphases between SmC_A^* and SmC^* but also the the staircase character of SmC_α^* emerging just below SmA, if we take account of the discrete flexoelectric polarization appropriately in addition to the ordinary one.