Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum-Classical Crossover and Apparent Metal-Insulator Transition in a
  Weakly Interacting 2D Fermi Liquid   We report the observation of a parallel magnetic field induced
metal-insulator transition (MIT) in a high-mobility two-dimensional electron
gas (2DEG) for which spin and localization physics most likely play no major
role. The high-mobility metallic phase at low field is consistent with the
established Fermi liquid transport theory including phonon scattering, whereas
the insulating phase at higher field shows a large negative temperature
dependence at resistances much smaller than the quantum of resistance, $h/e^2$.
We argue that this observation is a direct manifestation of a quantum-classical
crossover arising predominantly from the magneto-orbital coupling between the
finite width of the 2DEG and the in-plane magnetic field.

28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
2
The categories of this paper are: math
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga