Excitability and Defect-Mediated Turbulence in Nematic Liquid Crustal
نویسندگان
چکیده
We report the observation of one-arm spiral waves and of turbulence states in a nematic slab subjected to an external forcing These one-arm spiral waves constitute a close analog to the spiral waves observed m chemical and biological excitable media. Those results were obtained by adding a small vertical magnetic field on the experimental apparatus described m iii, in which double-arm spiral waves were observed m a sample with homeotropic alignment. We also describe a Gmzburg-Landau dynamical model accounting for the main kinds of
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