ISSN:
1434-6036
Keywords:
PACS. 47.54.+r Pattern selection; pattern formation – 61.30.-v Liquid crystals – 47.20.Ky Nonlinearity (including bifurcation theory)
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract: We develop a characterization method of electroconvection structures in a planar nematic liquid crystal layer by a study of the electric current transport. Because the applied potential difference has a sinusoidal time dependence, we define two electric Nusselt numbers corresponding to the in-phase and out-of-phase components of the current. These Nusselt numbers are predicted theoretically using a weakly nonlinear analysis of the standard model. Our measurements of the electric current confirm that both numbers vary linearly with the distance from onset until the occurence of secondary transitions. A systematic comparison between our theoretical and experimental results, using no adjusted parameters, demonstrates moderate agreement, but discrepancies remain. Electric transport measurements during electroconvection represent a quantitative test of the standard model completely independent from optical probes. Thus, the technique described here can be a useful complement to traditional structural measurements.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1140/epjb/e20020121
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