Experimental realization of coherent dark-state magnetometers A. Nagel, L. Graf, A. Naumov, E. Mariotti, V. Biancalana, D. Meschede and R. Wynands Europhys. Lett., 44 1 (1998) 31-36 Published online: 01 September 2002 DOI: 10.1209/epl/i1998-00430-0