Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Thermodynamic magnetization of a strongly correlated two-dimensional
  electron system   We measure thermodynamic magnetization of a low-disordered, strongly
correlated two-dimensional electron system in silicon. Pauli spin
susceptibility is observed to grow critically at low electron densities -
behavior that is characteristic of the existence of a phase transition. A new,
parameter-free method is used to directly determine the spectrum
characteristics (Lande g-factor and the cyclotron mass) when the Fermi level
lies outside the spectral gaps and the inter-level interactions between
quasiparticles are avoided. It turns out that, unlike in the Stoner scenario,
the critical growth of the spin susceptibility originates from the dramatic
enhancement of the effective mass, while the enhancement of the g-factor is
weak and practically independent of the electron density.

18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int