Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Longitudinal SDW order in a quasi-1D Ising-like quantum antiferromagnet   From neutron diffraction measurements on a quasi-1D Ising-like Co$^{\rm 2+}$
spin compound BaCo$_{\rm 2}$V$_{\rm 2}$O$_{\rm 8}$, we observed an appearance
of a novel type of incommensurate ordering in magnetic fields. This ordering is
essentially different from the N{\' e}el-type ordering, which is expected for
the classical system, and is caused by quantum fluctuation inherent in the
quantum spin chain. A Tomonaga-Luttinger liquid (TLL) nature characteristic of
the gapless quantum 1D system is responsible for the realization of the
incommensurate ordering.

22
The categories of this paper are: chao-dyn
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The categories of this paper are: acc-phys
1
The categories of this paper are: cs
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org