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arXiv · 1511.05100

Accessing the $\rm 5S_{1/2} \rightarrow 5D_{5/2}$ two-photon transition in Rb using a diode laser system

Ketan D. Rathod·Vasant Natarajan
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Abstract

We report observation of the $\rm 5S_{1/2} \rightarrow 5D_{5/2}$ two-photon transition in Rb vapor at 778 nm, using an external cavity diode laser system and a heated vapor cell. The spectra in the two isotopes show well-resolved hyperfine transitions. The peaks are Doppler free, and have a Lorentzian lineshape with a typical linewidth of 2.2 MHz. This linewidth is larger than the natural linewidth of 300 kHz, but is still 5--10 times smaller than the linewidth for single-photon transitions in the D$_2$ line. Since the absolute frequency of this transition is measured with 8 kHz precision, it can form a better secondary reference in the optical regime compared to the D$_2$ line.

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Ketan D. Rathod, Vasant Natarajan. 2015-11-13. Accessing the $\rm 5S_{1/2} \rightarrow 5D_{5/2}$ two-photon transition in Rb using a diode laser system. https://arxiv.org/abs/1511.05100

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