We propose a Ramsey interferometry experiment using an entangled state of N atoms to approach the Heisenberg limit for the estimation of an atomic phase shift if the atom number parity is perfectly determined. In a more realistic situation, due to statistical fluctuations of the atom source and the finite detection efficiency, the parity is unknown. We then achieve about half the Heisenberg limit. The scheme involves an ensemble of circular Rydberg atoms which dispersively interact successively with two initially empty microwave cavities. The scheme does not require very high-Q cavities. An experimental realization with about ten entangled Rydberg atoms is achievable with a state of art apparatus.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
Document Type: Research Article
Dipartimento di Fisica, Università di Camerino, I-62032 Camerino (MC), Italy
Laboratoire Kastler Brossel, Département de Physique de l'Ecole Normale Supérieure, France
July 1, 2007
More about this publication?