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Undulation instabilities in the meniscus of smectic membranes
J C Loudet1, P V Dolganov, P Patrício
1Université Bordeaux 1, CNRS, Centre de Recherche Paul Pascal, Avenue A. Schweitzer F-33600 Pessac, France.
Physical Review Letters
|April 8, 2011
Summary
Ferroelectric smectic-C* films exhibit periodic undulations at the air interface, forming striped patterns. These structures are linked to meniscus thickness and temperature, disappearing in the smectic-A phase.
Area of Science:
- Physics
- Materials Science
- Soft Matter Physics
Background:
- Freestanding ferroelectric smectic-C* films exhibit complex interfacial phenomena.
- Understanding meniscus behavior is crucial for controlling film properties.
Purpose of the Study:
- To characterize the undulated structures observed in the meniscus of ferroelectric smectic-C* films.
- To investigate the relationship between these structures, film properties, and environmental factors.
Main Methods:
- Optical microscopy
- Phase shifting interferometry
- Atomic force microscopy
Main Results:
- Periodic undulations were identified at the smectic-air interface, forming a striped pattern.
- This pattern was absent in the untilted smectic-A phase.
- Modulation amplitude and wavelength were found to depend on meniscus thickness.
Conclusions:
- The observed periodic structures are attributed to undulations of the smectic-air interface.
- A model was proposed to qualitatively explain the temperature evolution of these phenomena.
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