Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Gigantic magnetoelectric effect caused by magnetic-field-induced canted
  antiferromagnetic-paramagnetic transition in quasi-two-dimensional
  Ca$_2$CoSi$_2$O$_7$ crystal   We have investigated the magnetic and dielectric properties of
Ca$_2$CoSi$_2$O$_7$ crystal. The dielectricity and magnetism of
Ca$_2$CoSi$_2$O$_7$ are strongly coupled below a canted antiferromagnetic
transition temperature ($T_{\rm N}$): Magnetic fields induce electric
polarization below $T_{\rm N}$. Interestingly, the magnetic-field-induced
electric polarization is detected even without poling electric fields. Below
$T_{\rm N}$, a canted antiferromagnetic-paramagnetic transition is induced by
magnetic fields. The large magnetocapacitance is observed around $T_{\rm N}$.
The origin of the large magnetocapacitance is due to the magnetic-field-induced
the canted antiferromagnetic-paramagnetic transition.

13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th