Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optical conductivity near finite-wavelength quantum criticality   We study the optical conductivity sigma(Omega) of an electron system near a
quantum-critical point with finite-wavelength ordering. sigma(Omega) vanishes
in clean Galilean-invariant systems, unless electrons are coupled to dynamical
collective modes, which dissipate the current. This coupling introduces a
nonuniversal energy scale. Depending on the parameters of each specific system,
a variety of responses arise near criticality: scaling peaks at a temperature-
and doping-dependent frequency, peaks at a fixed frequency, or no peaks to be
associated with criticality. Therefore the lack of scaling in the far-infrared
conductivity in cuprates does not necessarily call for new concepts of quantum
criticality.

25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th