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arXiv · 1701.06015

Parametric wave mixing enhanced by velocity insensitive two-photon excitation in Rb vapour

Alexander M. Akulshin·Dmitry Budker·Russell J. McLean
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Abstract

We demonstrate how the orientation of the Rb cell can significantly affect the intensity and spectral characteristics of both the frequency up- and down-converted fields generated by nonlinear processes in Rb vapour. The efficiency of parametric wave mixing in Rb vapour excited to the 5D5/2 level by two-colour resonant laser light can be significantly increased by seeding the excitation region with coherent and directional radiation at 5.23 um that is resonant with the population inverted 5D5/2-6P3/2 transition. It has been shown that the process of velocity insensitive two-photon excitation is central to understanding the observed coherent blue and mid-IR light enhancements and that the velocity insensitive and velocity selective two-photon excitations could produce two co-existing but spectrally and spatially distinguishable mid-IR fields at 5.23 um.

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Alexander M. Akulshin, Dmitry Budker, Russell J. McLean. 2017-01-21. Parametric wave mixing enhanced by velocity insensitive two-photon excitation in Rb vapour. https://doi.org/10.1364/josab.34.001016

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