Return to the Origin as a Probe of Atomic Phase Coherence
  We report on the observation of the coherent enhancement of the return probability ("enhanced return to the origin" , ERO) in a periodically kicked cold-atom gas. By submitting an atomic wave packet to a pulsed, periodically shifted laser standing wave, we induce an oscillation of ERO in time and explain it in terms of a periodic, reversible dephasing in the weak-localization interference sequences responsible for ERO. Monitoring the temporal decay of ERO, we exploit its quantum coherent nature to quantify the decoherence rate of the atomic system. 
Cl\'ement Hainaut (PhLAM), Isam Manai (PhLAM), Radu Chicireanu   (PhLAM), Jean-Fran\c{c}ois Cl\'ement (PhLAM), Samir Zemmour...
cond-mat.dis-nn quant-ph