Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum phase diagram of a spin-1/2 antiferromagnetic chain with
  magnetic impurity   We present the renormalization group (RG) flow diagram of a spin-half
antiferromagnetic chain with magnetic impurity and one altered link. In this
two parameters (competing interactions) model, one can find the complex phase
diagram with many interesting fixed points. There is no evidence of
intermediate stable fixed point in weak coupling phase. It may arise at the
strong coupling phase. Depending on the strength of couplings the phases
correspond either to a decoupled spin with Curie law behavior or a
logarithmically diverging impurity susceptibility as in the two channel Kondo
problem.

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The categories of this paper are: mtrl-th
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The categories of this paper are: q-alg
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The categories of this paper are: nlin
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The categories of this paper are: solv-int
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The categories of this paper are: chem-ph
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The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: acc-phys
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The categories of this paper are: gr-qc
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The categories of this paper are: hep-ex
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The categories of this paper are: chao-dyn
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-lat
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The categories of this paper are: math-ph