Journal of Physics B Atomic Molecular and Optical Physics

Suppressing decoherence of spin waves in a warm atomic vapor by applying a guiding magnetic field

Long Tian, Shujing Li, Zhiying Zhang, Hai Wang

Published Jan 13, 2015• 1 citation

Abstract

Abstract We report an experimental and theoretical investigation to extend lifetimes of light storages by applying guiding magnetic fields in a room-temperature atomic vapor. The storages are based on dynamic electromagnetically induced transparency. Retrieval efficiencies versus storage time are experimentally measured for different strengths of the guiding magnetic fields. The measured results show that the 1/ e storage times are ∼6 μ s and ∼59 μ s for the guiding field B 0z = 0 and B 0z = 93 mG, respectively. Physical processes causing decoherence in an atomic ensemble have been discussed and analyzed. A theory model which is used to evaluate the decoherence caused by fluctuations of transverse magnetic fields is developed. Based on this evaluation, the fact that storage lifetimes can be increased by applying guiding magnetic fields is well explained.

DOI: 10.1088/0953-4075/48/3/035506

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