Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonlinear magnetoinductive waves and domain walls in composite
  metamaterials   We describe novel physics of nonlinear magnetoinductive waves in left-handed
composite metamaterials. We derive the coupled equations for describing the
propagation of magnetoinductive waves, and show that in the nonlinear regime
the magnetic response of a metamaterial may become bistable. We analyze
modulational instability of different nonlinear states, and also demonstrate
that nonlinear metamaterials may support the propagation of domain walls
(kinks) connecting the regions with the positive and negative magnetization.

1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
16
The categories of this paper are: stat