Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic phase diagram of three-dimensional diluted Ising
  antiferromagnet Ni$_{0.8}$Mg$_{0.2}$(OH)$_{2}$   $H$-$T$ diagram of 3D diluted Ising antiferromagnet
Ni$_{c}$Mg$_{1-c}$(OH)$_{2}$ with $c$ = 0.8 has been determined from
measurements of SQUID DC magnetization and AC magnetic susceptibility. At $H$ =
0, this compound undergoes two magnetic phase transitions: an antiferromagnetic
(AF) transition at the N\'{e}el temperature $T_{N}$ (= 20.7 K) and a reentrant
spin glass (RSG) transition at $T_{RSG}$ ($\approx$ 6 K). The $H$-$T$ diagram
consists of the RSG, spin glass (SG), and AF phases. These phases meet a
multicritical point $P_{m}$ ($H_{m}$ = 42 kOe, $T_{m}$ = 5.6 K). The
irreversibility of susceptibility defined by $\delta$ (= $\chi_{FC} -
\chi_{ZFC}$) shows a negative local minimum for 10 $\leq H \leq$ 35 kOe,
suggesting the existence of possible glassy phase in the AF phase. A broad peak
in $\delta$ and $\chi^{\prime \prime}$ at $H \geq$ 20 kOe for $T_{N}(c=0.8,H)
\leq T \leq T_{N}(c=1,H=0)$ (= 26.4 K) suggests the existence of the Griffiths
phase.

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The categories of this paper are: adap-org
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The categories of this paper are: funct-an
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The categories of this paper are: cmp-lg
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The categories of this paper are: mtrl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: chem-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: physics
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The categories of this paper are: astro-ph
2
The categories of this paper are: math
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The categories of this paper are: q-bio
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The categories of this paper are: eess
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The categories of this paper are: nucl-ex
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The categories of this paper are: quant-ph