Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optical probing of correlation driven liquid-to-insulator transition in
  2D electron gas   We study the quantum Hall liquid and the metal-insulator transition in a high
mobility two dimensional electron gas, by means of photoluminescence and
magneto-transport. In the integer and fractional regime at nu > 1/3, analyzing
the emission energy dispersion we probe the magneto-Coulomb screening and the
hidden symmetry of the electron liquid. In the fractional regime above above nu
=1/3 the system undergoes the metal-to-insulator transition, and in the
insulating phase the dispersion becomes linear with evidence of an increased
renormalized mass.

22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys