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arXiv · 0911.0812

Enhanced frequency up-conversion in Rb vapor

Abstract

We demonstrate highly efficient generation of coherent 420nm light via up-conversion of near-infrared lasers in a hot rubidium vapor cell. By optimizing pump polarizations and frequencies we achieve a single-pass conversion efficiency of 260% per Watt, significantly higher than in previous experiments. A full exploration of the coherent light generation and fluorescence as a function of both pump frequencies reveals that coherent blue light is generated close to 85Rb two-photon resonances, as predicted by theory, but at high vapor pressure is suppressed in spectral regions that do not support phase matching or exhibit single-photon Kerr refraction. Favorable scaling of our current 1mW blue beam power with additional pump power is predicted.

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A. Vernier, S. Franke-Arnold, E. Riis, A. S. Arnold. 2010-07-30. Enhanced frequency up-conversion in Rb vapor. https://doi.org/10.1364/oe.18.017020

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