Title
Surface effects on phases transitions in smectic membranes
Abstract
In liquid crystal materials, frustration between competing interactions and thermal fluctuation
results in the observation of many different phases (up to 5) in a relatively narrow
temperature window (usually about 30K). Identifying the interactions as well as finding
out the nature of those interactions that stabilize those phases is a very important and
interesting question. In this thesis, we study the interlayer interactions in smectic liquid
crystal materials through the study of surface effects on the phase transition in smectic
liquid crystal films.
Elevated surface interactions in liquid crystal materials result in surface transitions
higher in temperature than the bulk transitions. In the free standing film geometry
employed in our research, the nature of the surface order (surface transition temperature,
number of surface layers, surface critical exponent, etc.) are intrinsic properties of the
system.
With the surfaces ordered before the rest of the sample, the interior transitions take
place under the effective field created by the ordered surfaces. By studying the effects of
this surface field on the interior transitions, as well as the interactions between surface
layers and interior layers, and the interactions between the surface layers, we are able to obtain valuable information about the nature of the interlayer interactions in smectic
liquid crystal materials. Our results also provide new insights into the nature of the
surface transitions in the ordered surface region of the phase diagram.
Description
University of Minnesota Ph.D. dissertation. May 2011. Major: Physics. Advisor: Cheng-Cher Huang. 1 computer file (PDF); viii, 89 pages.
Suggested Citation
Pan, LiDong.
(2011).
Surface effects on phases transitions in smectic membranes.
Retrieved from the University of Minnesota Digital Conservancy,
https://hdl.handle.net/11299/151408.