Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Why stripes? Spontaneous formation of inhomogeneous structures due to
  elastic interactions   We argue that elastic interactions between ions in different valence states
can play an essential role in stabilization of stripes(or 2D "sheets")in doped
oxides. These interactions are in general long-range and anisotropic
(attractive in certain directions and repulsive in others). This can naturally
give rise to stripe-like structures in insulating materials. We illustrate this
general idea with certain specific examples and show that the situation can be
described by the Ising model with anisotropic interactions. The case of
anisotropic impurities, relevant e.g. for manganites, is also briefly
discussed.

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The categories of this paper are: patt-sol
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The categories of this paper are: acc-phys
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The categories of this paper are: mtrl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: quant-ph
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The categories of this paper are: solv-int
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-ex
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The categories of this paper are: stat
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The categories of this paper are: gr-qc
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The categories of this paper are: econ
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The categories of this paper are: eess
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The categories of this paper are: ao-sci
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The categories of this paper are: astro-ph