Article

Observation of Dark State Polariton Collapses and Revivals

School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430, USA.
Physical Review Letters (Impact Factor: 7.51). 02/2006; 96(3):033601. DOI: 10.1103/PhysRevLett.96.033601
Source: PubMed

ABSTRACT

By time-dependent variation of a control field, both coherent and single-photon states of light are stored in, and retrieved from, a cold atomic gas. The efficiency of retrieval is studied as a function of the storage time in an applied magnetic field. A series of collapses and revivals is observed, in very good agreement with theoretical predictions. The observations are interpreted in terms of the time evolution of the collective excitation of atomic spin wave and light wave, known as the dark-state polariton.

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Available from: Thierry Chanelière, Feb 03, 2016
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    • "In a uniform magnetic field, undamped revivals of the dark-state polariton should occur at times equal to nT L , where T L is the Larmor period for level |a or |b and n can be either integer or half-integer, depending on the direction of the magnetic field relative to the light beam geometry (a synopsis of these ideas is given in the Supplementary Information, with the full theory presented in Ref.[29]). We have conducted separate experiments with an externally applied magnetic field [30], which suggest that the collapse in the present experiment is likely due to magnetic field gradients and/or ac fields at the level of a few tens of mG. However, more extensive investigations to quantitatively determine the temporal and spatial structure of the residual magnetic field, and the various contributions to it, are ongoing. "
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