Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Singlet Ground State and Magnetization Plateaus in Ba$_3$Mn$_2$O$_8$   Magnetic susceptibility and the magnetization process have been measured in
\green polycrystal. In this compound, the magnetic manganese ion exists as
Mn$^{5+}$ in a tetrahedral environment, and thus the magnetic interaction can
be described by an S=1 Heisenberg model. The ground state was found to be a
spin singlet with an excitation gap $\Delta/k_{\rm B}=11.2$ K. Magnetization
plateaus were observed at zero and at half of the saturation magnetization.
These results indicate that the present system can be represented by a coupled
antiferromagnetic dimer model.

28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga