Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High Frequency Conductivity in the Quantum Hall Regime   We have measured the complex conductivity $\sigma_{xx}$ of a two-dimensional
electron system in the quantum Hall regime up to frequencies of 6 GHz at
electron temperatures below 100 mK. Using both its imaginary and real part we
show that $\sigma_{xx}$ can be scaled to a single function for different
frequencies and for all investigated transitions between plateaus in the
quantum Hall effect. Additionally, the conductivity in the variable-range
hopping regime is used for a direct evaluation of the localization length
$\xi$. Even for large filing factor distances $\delta \nu$ from the critical
point we find $\xi \propto \delta \nu^{-\gamma}$ with a scaling exponent
$\gamma=2.3$.

15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess
13
The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc