Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Crossover Between Flexoelectric Stripe Patterns and Electroconvection in
  Hybrid Aligned Nematics   We report experimental and theoretical results on the flexoelectric
instability and crossover between flexoelectric domains and electroconvection
in a hybrid aligned nematic MBBA under d.c. voltage. At threshold a spatially
periodic flexoelectric deformation in the form of longitudinal domains (along
the planar director) was observed. With increasing voltage the director
deviation out of the initial plane becomes clearly detectable. Observations of
tracers show that hydrodynamic flow develops inside the flexoelectric stripe
pattern in the form of circular orbits perpendicular to the domain stripes.
With further increasing d.c. voltage electroconvection sets in in the form of
drifting oblique rolls inside the flexoelectric domains.

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The categories of this paper are: mtrl-th
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The categories of this paper are: supr-con
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The categories of this paper are: adap-org
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The categories of this paper are: alg-geom
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The categories of this paper are: q-alg
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The categories of this paper are: astro-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: cond-mat
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The categories of this paper are: patt-sol
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The categories of this paper are: chao-dyn
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The categories of this paper are: plasm-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: eess
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The categories of this paper are: q-bio
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The categories of this paper are: bayes-an