Flexoelectricity and competition of time scales in electroconvection
نویسندگان
چکیده
منابع مشابه
Flexoelectricity and competition of time scales in electroconvection.
An unexpected type of behavior in electroconvection (EC) has been detected in nematic liquid crystals (NLCs) under the condition of comparable time scales of the director relaxation and the period of the driving ac voltage. The studied NLCs exhibit standard EC (s-EC) at the onset of the instability, except one compound in which nonstandard EC (ns-EC) has been detected. In the relevant frequency...
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For many years it has been commonly accepted that electroconvection (EC) as primary instability in nematic liquid crystals for the "classical" planar geometry requires a positive anisotropy of the electric conductivity, sigma(a), and a slightly negative dielectric anisotropy, epsilon(a). This firm belief was supported by many experimental and theoretical studies. Recent experiments, which have ...
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ژورنال
عنوان ژورنال: Physical Review E
سال: 2008
ISSN: 1539-3755,1550-2376
DOI: 10.1103/physreve.78.036306