Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Excitation spectra and ground state properties of the layered spin-1/2
  frustrated antiferromagnets Cs_2CuCl_4 and Cs_2CuBr_4   We use series expansion methods to study ground- and excited-state properties
in the helically ordered phase of spin-1/2 frustrated antiferromagnets on an
anisotropic triangular lattice. We calculate the ground state energy, ordering
wavevector, sublattice magnetization and one-magnon excitation spectrum for
parameters relevant to Cs_2CuCl_4 and Cs_2CuBr_4. Both materials are modeled in
terms of a Heisenberg model with spatially anisotropic exchange constants; for
Cs_2CuCl_4 we also take into account the additional Dzyaloshinskii-Moriya (DM)
interaction. We compare our results for Cs_2CuCl_4 with unpolarized neutron
scattering experiments and find good agreement. In particular, the large
quantum renormalizations of the one-magnon dispersion are well accounted for in
our analysis, and inclusion of the DM interaction brings the theoretical
predictions for the ordering wavevector and the magnon dispersion closer to the
experimental results.

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The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
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The categories of this paper are: q-fin
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The categories of this paper are: solv-int
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The categories of this paper are: acc-phys
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The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: hep-th
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The categories of this paper are: math-ph
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The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
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The categories of this paper are: bayes-an