Polarization squeezing with cold atoms
Résumé
We study the interaction of a nearly resonant linearly polarizedlaser beam with a cloud of cold cesium atoms in a high finesseoptical cavity. We show theoretically and experimentally that thecross-Kerr effect due to the saturation of the optical transitionproduces quadrature squeezing on both the mean field and theorthogonally polarized vacuum mode. An interpretation of thisvacuum squeezing as polarization squeezing is given and a methodfor measuring quantum Stokes parameters for weak beams via a localoscillator is developed.