Electroconvection Patterns in Smectic Films at and Above Onset
Electroconvection Patterns in Smectic Films at and Above Onset
Physica A, 239, 189 (1997).
Samuel S. Mao and John R. de Bruyn
Department of Physics
Memorial University of Newfoundland,
St. John's, Newfoundland, Canada A1B 3X7
Stephen W. Morris
Department of Physics and Erindale College,
University of Toronto, 60 St. George St., Toronto, Ontario, Canada M5S 1A7.
We have studied patterns of electrically-driven convective vortices in
thin freely-suspended films of smectic liquid crystal at and above the
onset of convection. 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 find values for the dimensionless
length and time scales of the Ginzburg-Landau equation.
