Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effect of Chemical Pressure on the Magnetic Transition of Multiferroic
  Ca-BiFeO3   Multiferroic BiFeO3 ceramics have been doped with Ca. The smaller ionic size
of Ca compared with Bi means that doping acts as a proxy for hydrostatic
pressure, at a rate of 1%Ca=0.3GPa. It is also found that the magnetic Neel
temperature (TNeel) increases as Ca concentration increases, at a rate of 0.66K
per 1%Ca (molar). Based on the effect of chemical pressure on TNeel, we argue
that applying hydrostatic pressure to pure BiFeO3 can be expected to increase
its magnetic transition temperature at a rate around ~2.2K/GPa. The results
also suggest that pressure (chemical or hydrostatic) could be used to bring the
ferroelectric critical temperature, Tc, and the magnetic TNeel closer together,
thereby enhancing magnetoelectric coupling, provided that electrical
conductivity can be kept sufficiently low.

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The categories of this paper are: dg-ga
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The categories of this paper are: chem-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: cs
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The categories of this paper are: econ
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The categories of this paper are: math
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The categories of this paper are: supr-con
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The categories of this paper are: patt-sol
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ex
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The categories of this paper are: nucl-ex
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The categories of this paper are: adap-org
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The categories of this paper are: solv-int
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The categories of this paper are: q-alg
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The categories of this paper are: q-fin
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The categories of this paper are: gr-qc