Eur. Phys. J. D 5, 301-305 (1999)
https://doi.org/10.1007/s100530050259

Twin-correlations in atoms

Institute of Physics and Astronomy, University of Aarhus, 8000 Å rhus C, Denmark

Received: 14 May 1998
Revised: 10 August 1998
Accepted: 8 October 1998
Published online: 15 February 1999

Abstract

We discuss the possibility of preparing an atomic sample of atoms with minimum fluctuations in the difference between populations of two levels. A first scheme involves absorption of twin beams of light, and it presents a variant of a recent proposal for atomic spin squeezing within an excited state manifold [Kuzmich et al., Phys. Rev. Lett. 79, 4782 (1997)]. A second scheme involves atoms with two stable states, and we suggest that by use of quantum non-demolition detection and feed-back optical pumping, we may ensure a perfect agreement between the number of atoms in these two states.