Inspection of a magneto-optical trap via electromagnetically induced absorption

Electromagnetically induced absorption (EIA) was observed for the first tim e on a sample of Rb-85 in a magnetooptical trap using low intensity cw copr opagating pump and probe optical fields. Narrow resonances revealing the de pendence of the ground-state Zeeman sublevels energy structure on the quadr upolar magnetic field and the trapping optical field intensity at different trap positions, were observed. Coherence resonances as narrow as 30 kHz we re obtained under low trapping field intensities. The use of EIA spectrosco py for the magnetic field mapping of cold atomic samples is illustrated. (C ) 2001 Published by Elsevier Science B.V.