Measurement of the $4S_{1/2}\to 6S_{1/2}$ transition frequency in atomic potassium via direct frequency comb spectroscopy

Abstract

We present an experimental determination of the $4S_{1/2}\to 6S_{1/2}$ transition frequency in atomic potassium, ${}^{39}$K, using direct frequency comb spectroscopy. The output of a stabilized optical frequency comb was used to excite a thermal atomic vapor. The repetition rate of the frequency comb was scanned and the transitions were excited using step-wise two-photon excitation. The center of gravity frequency for the transition was found to be ${\nu }_{\text{cog}}=822951698.09(13)$ MHz and the measured hyperfine $A$ coefficient of the $6S_{1/2}$ state was $21.93(11)$ MHz. The measurements are in agreement with previous values and represent an improvement by a factor of 700 in the uncertainty of the center of gravity measurement.

7 pages, 4 figures

Cited by in corpus (1)

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