Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonlinear quantum optics for spinor slow light   We investigate quantum nonlinear effects at a level of individual quanta in a
double tripod atom-light coupling scheme involving two atomic Rydberg states.
In such a scheme the slow light coherently coupled to strongly interacting
Rydberg states represents a two-component or spinor light. The scheme provides
additional possibilities for the control and manipulation of light quanta. A
distinctive feature of the proposed setup is that it combines the spin-orbit
coupling for the spinor slow light with an interaction between the photons,
enabling generation of the second probe beam even when two-photon detuning is
zero. Furthermore, the interaction between the photons can become repulsive if
the one-photon detunings have opposite signs. This is different from a single
ladder atom-light coupling scheme, in which the interaction between the photons
is attractive for both positive and negative detunings, as long as the Rabi
frequency of the control beam is not too large.

9
The categories of this paper are: nlin
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc