Electroconvection Patterns in Smectic Lms at and above Onset
نویسندگان
چکیده
We have studied patterns of electrically-driven convective vortices in thin freely-suspended lms of smectic liquid crystal at and above the onset of con-vection. We present measurements of the convective amplitude above onset, the spatial variation of the amplitude due to the presence of end walls, and the relaxation of the amplitude following a sudden change in the experimental control parameter. Our experimental results are shown to agree with predictions based on the Ginzburg-Landau equation, and we nd values for the dimensionless length and time scales of the Ginzburg-Landau equation.
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