Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Heralded single-magnon quantum memory for photon polarization states   We demonstrate a heralded quantum memory based on mapping of a photon
polarization state onto a single collective-spin excitation (magnon) shared
between two spatially overlapped atomic ensembles. The polarization fidelity is
measured by quantum state tomography to be above 90(2)% for any input
polarization, which far exceeds the classical limit of 2/3. The process also
constitutes a quantum non-destructive probe that detects and regenerates a
photon without touching its - potentially undetermined - polarization.

26
The categories of this paper are: bayes-an
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
19
The categories of this paper are: eess
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
1
The categories of this paper are: cs