Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dynamical charge inhomogeneity and crystal-field fluctuations for 4f
  ions in high-Tc cuprates   The main relaxation mechanism of crystal-field excitations in rare-earth ions
in cuprates is believed to be provided by the fluctuations of crystalline
electric field induced by a dynamic charge inhomogeneity generic for the doped
cuprates. We address the generalized granular model as one of the model
scenario for such an ingomogeneity where the cuprate charge subsystem remind
that of Wigner crystal with the melting transition and phonon-like positional
excitation modes. Formal description of R-ion relaxation coincides with that of
recently suggested magnetoelastic mechanism.

21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
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The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
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The categories of this paper are: solv-int
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The categories of this paper are: hep-lat
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph