Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Second harmonic generation in dielectric nanoparticles with different
  symmetries   In this work, we study second-harmonic generation a monocrystalline
nanoparticle with a non-centrosymmetric crystalline lattice. It was shown that
breaking the symmetry of the nanoparticle's shape can significantly affect the
second harmonic radiation pattern. We propose a method for explaining and
predicting the generated field for arbitrary nanoparticles and provide
selection rules for nanoparticles with several different symmetries.

25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
16
The categories of this paper are: stat
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
32
The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph