https://doi.org/10.1140/epjd/e2008-00160-9
Exact results on decoherence and entanglement in a system of N driven atoms and a dissipative cavity mode
Dipartimento di Fisica, Università di Milano, via
Celoria 16, 20133 Milano, Italy
Corresponding author: a federico.casagrande@mi.infn.it
Received:
30
April
2008
Revised:
19
June
2008
Published online:
8
August
2008
We solve the dynamics of an open quantum system where N strongly driven two-level atoms are equally coupled on resonance to a dissipative cavity mode. Analytical results are derived on decoherence, entanglement, purity, atomic correlations and cavity field mean photon number. We predict decoherence-free subspaces for the whole system and the N-qubit subsystem, the monitoring of quantum coherence and purity decay by atomic populations measurements, the conditional generation of atomic multi-partite entangled states and of cavity cat-like states. We show that the dynamics of atoms prepared in states invariant under permutation of any two components remains restricted within the subspace spanned by the completely symmetric Dicke states. We discuss examples and applications in the cases N=3,4.
PACS: 42.50.Pq – Cavity quantum electrodynamics; micromasers / 03.65.Yz – Decoherence; open systems; quantum statistical methods / 03.67.Bg – Entanglement production and manipulation
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2008