Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetisation of hole-doped CuO2 spin chains in Sr14-xCaxCu24O41   We report on magnetisation measurements of Sr14-xCaxCu24O41, with 0 <= x <=
12, in magnetic fields up to 16 T. The low temperature magnetic response of the
CuO2 spin chains changes strongly upon doping. For x = 0, the ground state with
nearly independent dimers is confirmed. Reduction of the number of holes in the
chains through Ca-doping leads to an additional contribution to the
magnetisation, which depends linearly on the magnetic field. Remarkably, the
slope of this linear contribution increases with the Ca content. We argue that
antiferromagnetic spin chains do not account for this behaviour but that the
hole dynamics might be involved.

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The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
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The categories of this paper are: solv-int
21
The categories of this paper are: adap-org
18
The categories of this paper are: econ
16
The categories of this paper are: stat
7
The categories of this paper are: hep-th
17
The categories of this paper are: q-fin