title: Critical fluctuations at the untilted-tilted phase transition in chiral smectic liquid crystals
abstract: The layer compression modulus B was measured near the Sm-A-Sm-C* and Sm-A-Sm-C(*)(A) transitions of chiral smectic liquid crystals. B shows a marked pretransitional softening due to the order parameter fluctuations above the phase transition. The width of the critical region of the Sm-A-Sm-C* and Sm-A-Sm-C(*)(A) transitions is smaller than that of the Sm-A-Sm-C(*)(alpha) transition. The critical exponents of B are in agreement with the theoretical description based on renormalization-group method. These results reveal that these transitions are not of the Landau mean-field type.
authors.affiliation: Department of Organic and Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152, Japan.
authors.initials: S
authors.lastname: Shibahara
authors.initials: J
authors.lastname: Yamamoto
authors.initials: Y
authors.lastname: Takanishi
authors.initials: K
authors.lastname: Ishikawa
authors.initials: H
authors.lastname: Takezoe