Origin of traveling rolls in electroconvection of nematic liquid crystals.

نویسندگان

  • Dennin
  • Treiber
  • Kramer
  • Ahlers
  • Cannell
چکیده

Electroconvection in nematic liquid crystals exhibits a Hopf bifurcation to traveling rolls for a wide parameter range. The model normally used to describe electroconvection fails to predict this. A recent theoretical extension, the weak-electrolyte model, incorporates the dissociation-recombination reaction of the ionic dopant in the sample and does predict a Hopf bifurcation for a range of parameter values. We present a quantitative experimental test of this theory using the nematic liquid crystal I52. Measured Hopf frequencies at the onset of convection agree well with the theory.

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عنوان ژورنال:
  • Physical review letters

دوره 76 2  شماره 

صفحات  -

تاریخ انتشار 1996