Magneto-optical effects and rf magnetic field detection in cold rubidium atoms

We present the results of our latest experiments on atomic coherences in cold atoms. Interaction of atoms with a near-resonant, linearly polarized light leads to an effective creation of long-lived ground-state Zeeman coherences which is observed through the nonlinear Faraday effect or free induction decay signals of the Larmor precession. Both optically and radiofrequency induced Zeeman coherences are observed, with relaxation rates around a 100 Hz.