Laser Physics Letters

A stable frequency standard based on the one-color two-photon 5 S –7 S transition of rubidium at 760 nm

Sandan Wang, Jinpeng Yuan, Lirong Wang, Liantuan Xiao, Suotang Jia

Published Dec 1, 2019• 10 citations

Abstract

Abstract We report an experimental investigation of the 5 S 1/2 –7 S 1/2 one-color two-photon transition in rubidium vapor with a single continuous-wave laser operating at 760 nm. By utilizing a robust intensity modulation method, high-resolution spectra with a signal-to-noise ratio of ~120 are obtained. A perfect match between experimental results and the theoretical analysis is obtained by characterizing the probability of a two-photon transition with vapor temperature and laser power. Moreover, the influence of electric dipole selection rules on the two-photon transition is also investigated by changing the polarization of the laser beam. Since the 5 S 1/2 –7 S 1/2 two-photon transition is insensitive to stray magnetic fields and has an extremely narrow linewidth, we confidently believe that it can provide a concrete frequency standard for quantum telecommunication in the S -band window (1480–1530 nm). Meanwhile, the atomic system at 760 nm will serve as a good candidate for a quantum repeater.

DOI: 10.1088/1612-202x/ab595c

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