Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optical and dc conductivities of cuprates: Spin-fluctuation scattering
  in the t-J model   A microscopic theory of the electrical conductivity $\sigma(\omega)$ within
the t-J model is developed. An exact representation for $\sigma(\omega)$ is
obtained using the memory-function technique for the relaxation function in
terms of the Hubbard operators, and the generalized Drude law is derived. The
relaxation rate due to the decay of charge excitations into particle-hole pairs
assisted by antiferromagnetic spin fluctuations is calculated in the
mode-coupling approximation. Using results for the spectral function of spin
excitations calculated previously, the relaxation rate and the optical and dc
conductivities are calculated in a broad region of doping and temperatures. The
reasonable agreement of the theory with experimental data for cuprates proves
the important role of spin-fluctuation scattering in the charge dynamics.

8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th