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Updated: May 4, 2026
20:38
AC Electrokinetic Phenomena Generated by Microelectrode Structures
Published on: July 29, 2008
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Persistent global power fluctuations near a dynamic transition in electroconvection
Tibor Tóth-Katona1, John R Cressman, Walter I Goldburg
1Department of Physics, Kent State University, P.O.B. 5190, Kent, Ohio 44242, USA. katona@physics.kent.edu
Summary
Global fluctuations in liquid crystals are caused by defect creation and annihilation. These defects, though spatially random, show long-lasting temporal correlations, similar to thermal plumes in convection.
Area of Science:
- Physics
- Soft Matter Physics
- Nonlinear Dynamics
Background:
- Electroconvection in liquid crystals exhibits complex dynamics.
- Understanding defect formation is crucial for characterizing system behavior.
Purpose of the Study:
- Investigate global fluctuations in power injection and light transmission in liquid crystals near electroconvection onset.
- Identify the source and characteristics of these fluctuations.
- Explore the relationship between defect dynamics and thermal plumes.
Main Methods:
- Experimental observation of liquid crystal behavior.
- Analysis of power injection and light transmission data.
- Correlation analysis to study temporal and spatial relationships.
Main Results:
- Fluctuations originate from the creation and annihilation of defects.
- Defect creation/annihilation events are spatially uncorrelated.
- These events exhibit long-term temporal correlations.
- A strong link exists between defect dynamics and thermal plumes in Rayleigh-Bénard convection.
Conclusions:
- Defect dynamics are the primary driver of fluctuations in this system.
- The observed temporal correlations suggest long-range interactions or memory effects.
- The analogy to thermal plumes provides insights into universal mechanisms in convective systems.
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