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Updated: Aug 29, 2026

Gradient Echo Quantum Memory in Warm Atomic Vapor
Published on: November 11, 2013
Slow diffusion of light in a cold atomic cloud
G Labeyrie1, E Vaujour, C A Müller
1Laboratoire Ondes et Désordre, FRE 2302 CNRS, 1361 route des Lucioles, F-06560 Valbonne, France. Guillaume.Labeyrie@inln.cnrs.fr
Abstract:
We study the diffusive propagation of multiply scattered light in an optically thick cloud of cold rubidium atoms illuminated by a quasiresonant laser beam. In the vicinity of a sharp atomic resonance, the energy transport velocity of the scattered light is almost 5 orders of magnitude smaller than the vacuum speed of light, reducing strongly the diffusion constant. We verify the theoretical prediction of a frequency-independent transport time around the resonance. We also observe the effect of the residual velocity of the atoms at long times.
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