Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Suppression of low-frequency noise in two-dimensional electron gas at
  degenerately doped Si:P \delta-layers   We report low-frequency 1/f noise measurements of degenerately doped Si:P
\delta-layers at 4.2K. The noise was found to be over six orders of magnitude
lower than that of bulk Si:P systems in the metallic regime and is one of the
lowest values reported for doped semiconductors. The noise was found to be
nearly independent of magnetic field at low fields, indicating negligible
contribution from universal conductance fluctuations. Instead interaction of
electrons with very few active structural two-level systems may explain the
observed noise magnitude

9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
19
The categories of this paper are: eess
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg