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Updated: Jun 2, 2026

Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
Photon lifetime in a cavity containing a slow-light medium
T Lauprêtre1, C Proux, R Ghosh
1Laboratoire Aimé Cotton, CNRS-Université Paris Sud 11, 91405 Orsay Cedex, France. thomas.laupretre@lac.u‐psud.fr
Abstract:
We investigate experimentally the lifetime of the photons in a cavity containing a medium exhibiting strong positive dispersion. This intracavity positive dispersion is provided by a metastable helium gas at room temperature in the electromagnetically induced transparency regime, in which light propagates at a group velocity of the order of 10⁴ m·s⁻¹. The results definitely prove that the lifetime of the cavity photons is governed by the group velocity of light in the cavity and not its phase velocity.
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