Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optical reconstruction of collective density matrix of qutrit   Reconstruction of a quantum state is of prime importance for
quantum-information science. Specifically, means of efficient determination of
a state of atoms of room-temperature vapor may enable applications in quantum
computations and cryptography. To step toward such applications, here we
present a method of reconstruction of a collective density matrix of an atomic
ensemble, consisting of atoms with an $F=1$ ground state. Such a long-lived
state is often encountered in real systems (e.g., potassium, sodium, rubidium)
and hence may be practically utilized. Our theoretical treatment enables
derivation of explicit formulas relating optical signals (polarization rotation
and ellipticity change) with specific density-matrix elements. The analysis are
supported with numerical simulations, which allows to evaluate fidelity and
robustness of the algorithm. The tests show that our algorithm allows to obtain
the fidelity exceeded 0.95 even at noisy environment and/or significant atomic
manipulation imperfections.

1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph