Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Periodic Density Modulation Effects on a Correlated two-dimensional
  Composite Fermion System   We examine theoretically the effects caused by a periodic external potential
on the correlated motion of a two-dimensional electron system under strong
magnetic fields corresponding to a filling factor 1/2. To describe the
resulting complex dynamics, we adopt a composite fermion approach and we
determine in a two loop approximation the density-response function
$K_{00}(\bfq,\omega)$ and the compressibility. We show explicitly that the
long-wavelength limit of $K_{00}(\bfq,\omega)$ exhibits substantial anisotropic
behavior induced by the modulation, and that the system tends to be
incompressible in a direction orthogonal to the modulation as opposed to its
response along the modulation.

8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
16
The categories of this paper are: stat
2
The categories of this paper are: math
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th