Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Charge correlations in the weakly doped t-J model calculated by
  projection technique   We study frequency- and wave-vector dependent charge correlations in weakly
doped antiferromagnets using Mori-Zwanzig projection technique. The system is
described by the two-dimensional t-J model. The ground state is expressed
within a cumulant formalism which has been successfully applied to study
magnetic properties of the weakly doped system. Within this approach the ground
state contains independent spin-bag quasiparticles (magnetic polarons). We
present results for the charge-density response function and for the optical
conductivity at zero temperature for different values of t/J. They agree well
with numerical results calculated by exact diagonalization techniques. The
density response function for intermediate and large momenta shows a broad
continuum on energy scales of order of several t whereas the optical
conductivity for \omega > 0 is dominated by low energy excitations (at 1.5 - 2
J). We show that these weak-doping properties can be well understood by
transitions between excited states of spin-bag quasiparticles.

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The categories of this paper are: alg-geom
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-ex
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The categories of this paper are: atom-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: patt-sol
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The categories of this paper are: nlin
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The categories of this paper are: astro-ph
5
The categories of this paper are: gr-qc
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The categories of this paper are: bayes-an
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The categories of this paper are: q-bio
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ph
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The categories of this paper are: hep-th