Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: C-axis Raman spectra of a normal plane-chain bilayer cuprate and the
  pseudogap   We investigate the Raman spectra in the geometry where both incident and
scattered photon polarizations are parallel to the $\hat{z}$-direction, for a
plane-chain bilayer coupled via a single-particle tunneling $t_\perp$. The
Raman vertex is derived in the tight-binding limit and in the absence of
Coulomb screening, the Raman intensity can be separated into intraband
($\propto t_\perp^4$) and interband ($\propto t_\perp^2$) transitions. In the
small-$t_\perp$ limit, the interband part dominates and a pseudogap will appear
as it does in the conductivity. Coulomb interactions bring in a two-particle
coupling and result in the breakdown of intra- and interband separation.
Nevertheless, when $t_\perp$ is small, the Coulomb screening ($\propto
t_\perp^4$) has little effect on the intensity to which the unscreened
interband transitions contribute most. In general, the total Raman spectra are
strongly dependent on the magnitude of $t_\perp$.

23
The categories of this paper are: solv-int
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
3
The categories of this paper are: physics
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
1
The categories of this paper are: cs