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arXiv · 1506.06934

Suppression of ac Stark shift scattering rate due to non-Markovian behavior

Muzaffar Q. Lone·Tim Byrnes
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Abstract

The ac Stark shift in the presence of spontaneous decay is typically considered to induce an effective dephasing with a scattering rate equal to $ Γ_s |Ω|^2/Δ^2 $, where $ Γ_s $ is the spontaneous decay rate, $ Ω$ is the laser transition coupling, and $ Δ$ is the detuning. We show that under realistic circumstances this dephasing rate may be strongly modifed due to non-Markovian behavior. The non-Markovian behavior arises due to an effective modification of the light-atom coupling in the presence of the ac Stark shift laser. An analytical formula for the non-Markovian ac Stark shift induced dephasing is derived. We obtain that for narrow laser linewidths the effective dephasing rate is suppressed by a factor of $ Q^2$, where $ Q $ is the quality factor of the laser.

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Muzaffar Q. Lone, Tim Byrnes. 2015-06-23. Suppression of ac Stark shift scattering rate due to non-Markovian behavior. https://doi.org/10.1103/physreva.92.011401

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