Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Controllably releasing long-lived quantum memory for photonic
  polarization qubit into multiple separate photonic channels   We report an experiment in which long-lived quantum memories for photonic
polarization qubits (PPQs) are controllably released into any one of multiple
separate channels. The PPQs are implemented with an arbitrarily-polarized
coherent signal light pulses at the single-photon level and are stored in cold
atoms by means of electromagnetic-induced-transparency scheme. Reading laser
pulses propagating along the direction at a small angle relative to quantum
axis are applied to release the stored PPQs into an output channel. By changing
the propagating directions of the read laser beam, we controllably release the
retrieved PPQs into 7 different photonic output channels, respectively. At one
of the output channels, the measured maximum quantum-process fidelity for the
PPQs is 94.2% at storage time of t= 0.85ms. At storage time of 6 ms, the
quantum-process fidelity is still beyond 78%, the threshold for the violation
of the Bell inequality. The demonstrated controllable release of the stored
PPQs may extend the capabilities of the quantum information storage technique.

11
The categories of this paper are: hep-lat
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio