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Drastic effects of damping mechanisms on the third-order optical nonlinearity

Kazuki Koshino·Hajime Ishihara
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Abstract

We have investigated the optical response of superradiant atoms, which undergoes three different damping mechanisms: radiative dissipation ($γ_r$), dephasing ($γ_d$), and nonradiative dissipation ($γ_n$). Whereas the roles of $γ_d$ and $γ_n$ are equivalent in the linear susceptibility, the third-order nonlinear susceptibility drastically depends on the ratio of $γ_d$ and $γ_n$: When $γ_d \ll γ_n$, the third-order susceptibility is essentially that of a single atom. Contrarily, in the opposite case of $γ_d \gg γ_n$, the third-order susceptibility suffers the size-enhancement effect and becomes proportional to the system size.

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Kazuki Koshino, Hajime Ishihara. 2004-11-18. Drastic effects of damping mechanisms on the third-order optical nonlinearity. https://doi.org/10.1143/jpsj.74.2921

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