An ultrasonic investigation of the critical behaviour of the elastic moduli near the smectic C-smectic A phase transition

Abstract

Results for the frequency-temperature dependence of the elastic moduli and the longitudinal sound velocity near the S_C–S_A transition are reported. The measurements were made at frequencies in the range 0.15–27 MHz. The interpretation of the results obtained was made using the theory of critical dynamics taking into consideration the bare anisotropy.