Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Slow light based optical frequency shifter   We demonstrate experimentally and theoretically a controllable way of
shifting the frequency of an optical pulse by using a combination of spectral
hole burning, slow light effect, and linear Stark effect in a rare-earth-ion
doped crystal. We claim that the solid angle of acceptance of a frequency shift
structure can be close to $2\pi$, which means that the frequency shifter could
work not only for optical pulses propagating in a specific spatial mode but
also for randomly scattered light. As the frequency shift is controlled solely
by an external electric field, it works also for weak coherent light fields,
and can e.g. be used as a frequency shifter for quantum memory devices in
quantum communication.

23
The categories of this paper are: solv-int
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg