Eur. Phys. J. B 9, 461-469 (1999)
https://doi.org/10.1007/s100510050787

Competition between ferroelectric and flexoelectric polarization in freely suspended smectic films

¹ Institute of Physical Chemistry, University Marburg, 35032 Marburg, Germany
² Institute of Solid State Physics, Russian Academy of Sciences, 142432 Chernogolovka, Moscow District, Russia
³ School of Chemistry, The University, Hull HU6 7RX, UK

Received: 21 October 1998
Published online: 15 June 1999

Abstract

We report a detailed ellipsometric study of freely suspended films of chiral liquid-crystal compounds possessing smectic-A and smectic-C phases. In the temperature region between the smectic-A -smectic-C bulk and surface transitions, a discontinuous reconstruction of the tilt profile across the film is observed in the presence of a constant d.c. electric field. Comparison of the measured ellipsometric quantities with values calculated from model tilt profiles reveals a competition between a structure possessing a homogeneous tilt direction and large ferroelectric polarization and a structure with opposite tilt direction in the two film halfs and large flexoelectric polarization.