Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Anomalous magnetic suppression of spin relaxation in a two-dimensional
  electron gas in a GaAs/AlGaAs quantum well   We study the spin dynamics in a high-mobility two-dimensional electron gas
confined in a GaAs/AlGaAs quantum well. An unusual magnetic field dependence of
the spin relaxation is found: as the magnetic field becomes stronger, the spin
relaxation time first increases quadratically but then changes to a linear
dependence, before it eventually becomes oscillatory, whereby the longitudinal
and transverse times reach maximal values at even and odd filling Landau level
factors, respectively. We show that the suppression of spin relaxation is due
to the effect of electron gyration on the spin-orbit field, while the
oscillations correspond to oscillations of the density of states appearing at
low temperatures and high magnetic fields. The transition from quadratic to
linear dependence can be related to a transition from classical to Bohm
diffusion and reflects an anomalous behavior of the two-dimensional electron
gas analogous to that observed in magnetized plasmas.

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The categories of this paper are: astro-ph
1
The categories of this paper are: cs
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
11
The categories of this paper are: hep-lat