Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Eliashberg analysis of the optical conductivity in superconducting
  Pr$_2$CuO$_{x}$ ($x \simeq 4$)   Superconducting Pr$_2$CuO$_x$, $x\simeq 4$ films with $T^\prime$ structure
and a $T_c$ of 27 K have been investigated by millimeter-wave transmission and
broadband (infrared-to-ultraviolet) reflectivity measurements in the normal and
superconducting state. The results obtained by both experimental methods show a
consistent picture of the superconducting condensate formation below $T_c$. An
Eliashberg analysis of the data proves $d$-wave superconductivity and
unitary-limit impurity scattering of the charge carriers below $T_{c}$. The
derived electron-exchange boson interaction spectral function $I^2\chi(\omega)$
shows only marginal changes at the superconducting transition with the mass
enhancement factor $\lambda$, the first inverse moment of $I^2\chi(\omega)$,
being equal to 4.16 at 30 K and to 4.25 at 4 K.

30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
6
The categories of this paper are: astro-ph
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn