Abstract
We use dynamic light scattering to investigate the fluctuation modes of a chiral smectic-$A$ liquid crystal which exhibits a metastable one-dimensional modulation of the smectic layers parallel to the average layer plane. The modulation, which contains two components (a ``main'' and ``fine'' structure), breaks translational symmetry in the layer plane, and produces two new hydrodynamic fluctuation modes in addition to the director fluctuations. In a sufficiently large applied electric field, the modulation is destabilized: large amplitude fluctuations of the symmetry-restoring modes are observed. Both the frequency and dispersion of these modes change significantly from the zero field case. We present a phenomenological elastic theory, which quantitatively describes the measured dispersion of the mode frequencies and amplitudes, in both zero and high applied field. We also discuss how the transition from zero to high applied field might be understood in terms of recent theories of smectic phases with broken layer inversion symmetry, which predict a nontrivial renormalization of the elastic constants due to anharmonic fluctuations.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
