Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Carrier-density-controlled anisotropic spin susceptibility of
  two-dimensional hole systems   We have studied quantum-well-confined holes based on the Luttinger-model
description for the valence band of typical semiconductor materials. Even when
only the lowest quasi-two-dimensional (quasi-2D) subband is populated, the
static spin susceptibility turns out to be very different from the universal
isotropic Lindhard-function lineshape obtained for 2D conduction-electron
systems. The strongly anisotropic and peculiarly density-dependent spin-related
response of 2D holes at long wavelengths should make it possible to switch
between easy-axis and easy-plane magnetization in dilute magnetic quantum
wells. An effective g factor for 2D hole systems is proposed.

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The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
22
The categories of this paper are: chao-dyn
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The categories of this paper are: hep-th
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The categories of this paper are: cs
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The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex