Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Steep optical wave group velocity reduction and storage of light without
  electromagnetically induced transparency   We report experimental investigationd of optical pulse group velocity
reduction and probe pulse regeneration using a Raman scheme. The new scheme
which does not rely on the on-one-photon resonance electromagnetically induced
transparency (EIT), has many advantages over the conventional method which
critically relys on the transparency window created by an EIT process. We
demonstrate significant reduction of group velocity, less probe field loss,
reduced probe pulse distortion, and high probe pulse regeneration efficiency.

8
The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ