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Updated: Jun 22, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Topographic-pattern-induced homeotropic alignment of liquid crystals
Youngwoo Yi1, Giuseppe Lombardo, Neil Ashby
1Department of Physics and Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309-0390, USA.
Summary
Nanoimprinted polymer films with specific well dimensions control liquid crystal alignment. The depth/width ratio of nanoimprinted wells dictates whether rodlike liquid crystals align vertically, horizontally, or tilted.
Area of Science:
- Materials Science
- Soft Matter Physics
- Nanotechnology
Background:
- Liquid crystals (LCs) exhibit unique optical and electronic properties.
- Surface topography significantly influences LC alignment.
- Controlling LC orientation is crucial for display and photonic applications.
Purpose of the Study:
- To investigate the effect of nanoimprinted checkerboard patterns on calamitic liquid crystal alignment.
- To determine the relationship between well geometry (depth/width ratio) and LC orientation.
- To understand the transition from planar to homeotropic alignment in patterned polymer films.
Main Methods:
- Nanoimprint lithography to create checkerboard patterns on polymer films.
- Microscopy and optical techniques to observe liquid crystal alignment.
- Theoretical modeling and computer simulations to confirm experimental observations.
Main Results:
- Nanoimprinted checkerboard patterns induce vertical, horizontal, or tilted alignment of calamitic LCs.
- The depth/width ratio of the wells is the key parameter controlling LC orientation.
- Increasing elastic energy density in narrower wells overcomes surface anchoring, leading to homeotropic alignment.
Conclusions:
- Topographical patterning of polymer films offers a precise method for controlling liquid crystal alignment.
- The findings are applicable to both nematic and smectic liquid crystals.
- This work provides fundamental insights into surface-induced LC ordering and has implications for advanced optical devices.
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