Reentrant Distorted Sm C Observed under Electric Field in Ferroelectric Smectic Liquid Crystals, nOBAMBC

By using a partially degraded cell possessing T c gradient, we have visualized in a micrograph reentrant distorted Sm C * under an electric field; the fringe disappears in the middle where T c - T ∼0.25°C but can remain near the T c position. The E - T diagram thus obtained is different from that predicted by Michelson et al. and is explained by the effect of the tilt angle fluctuation. We have also found that, when the cell quality is not high, there appears a blue color in the vicinity of T c , though we could not clarify the cause of its appearance.