Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Plasmon-enhanced second harmonic generation in the laser-irradiated
  cubic metal nanoparticles   The plasmon-enhanced second harmonic generation in the subwavelength neutral
metal cubic nanoparticles is calculated for the first time in the hydrodynamic
and cold plasma approximations. The theory is developed that takes into account
all singularities of the electromagnetic field at the cubic nanoparticle
surface. The results are compared to the linear case for the nanocube and to
those for a spherical nanoparticle. In the latter case, they demonstrate very
strong enhancement of the local field strength and the second harmonic signal.

26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph