Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: All-optical reshaping of light pulses using $\chi^{(2)}$ media   We have developed a new method based on two cavities containing $\chi^{(2)}$
media to reshape optical pulses by an all-optical technique. The system is
entirely passive \emph{i.e.}, all the energy is brought by the incoming pulse
and uses two successive optical cavities with independent thresholds. The
output pulse is close to a rectangular shape. We show that this technique could
be extended to high bit rates and telecommunication wavelength using very small
cavities containing current nonlinear materials.

19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
15
The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
16
The categories of this paper are: stat