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arXiv · 1905.09484

Collimated UV light generation by two-photon excitation to a Rydberg state in Rb vapor

Mark Lam·Sambit B. Pal·Thibault Vogt·Christian Gross·Martin Kiffner·Wenhui Li
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Abstract

We use two continuous-wave (CW) laser beams of 780 nm and 515 nm to optically drive $^{85}$Rb atoms in a heated vapor cell to a low-lying Rydberg state 10D$_{5/2}$. We observe a collimated ultraviolet (UV) beam at 311 nm, corresponding to the transition frequency from the 11P$_{3/2}$ state to the 5S$_{1/2}$ state. This indicates the presence of a coherent four-wave mixing process, built up by two input laser fields as well as a terahertz (THz) radiation of 3.28 THz that is generated by amplified spontaneous emission between the 10D$_{5/2}$ and the 11P$_{3/2}$ states. We characterize the 311 nm UV light generation and its dependence on various physical parameters. This scheme could open up a new possibility for generating narrow-band THz waves as well as deep UV radiation.

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Mark Lam, Sambit B. Pal, Thibault Vogt, Christian Gross, Martin Kiffner, Wenhui Li. 2019-05-23. Collimated UV light generation by two-photon excitation to a Rydberg state in Rb vapor. https://doi.org/10.1364/ol.44.002931

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