Abstract
Under idealized conditions, electroconvection in a nematic liquid crystal sets in at a well-defined threshold of the driving ac voltage. Fluctuating convection rolls of a small amplitude below that threshold have been observed recently. The measurement of the amplitude of these fluctuations is described in detail in this paper. It is based on averaging the light intensity signals using the structure function and a quantitative analysis of the light deflection.
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Rehberg, I., Horner, F. & Hartung, G. The measurement of subcritical electroconvection. J Stat Phys 64, 1017–1023 (1991). https://doi.org/10.1007/BF01048811
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DOI: https://doi.org/10.1007/BF01048811