Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Field induced antiferromagnetism and $^{17}$O Knight shift anomaly in
  La$_2$CuO$_4$   We address the effect of the field induced antiferromagnetism in paramagnetic
state of the cuprate weak ferromagnet La$_2$CuO$_4$. The planar oxygen $^{17}$O
Knight shift is shown to be an effective tool to inspect the effects of
Dzyaloshinsky-Moriya coupling in cuprates in an external magnetic field. Field
induced antiferromagnetism and anisotropic antiferromagnetic contribution to
$^{17}$K explain the anomalies observed in $^{17}$O NMR in La$_2$CuO$_4$. The
experimental observation of antiferromagnetic contribution to the $^{17}$O
Knight shift provides probably the only way to find out the problem of the
sense of Dzyaloshinsky vector in cuprates.

24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
2
The categories of this paper are: math
23
The categories of this paper are: solv-int