Vuv frequency-comb spectroscopy of atomic xenon

Abstract

Direct frequency-comb spectroscopy of a single-photon transition ($5{p}^{6}\ensuremath{-}5{p}^{5}6s$) in ${}^{132}\mathrm{Xe}$ is performed with a vacuum ultraviolet (vuv) frequency comb at 147 nm. The vuv comb is generated from an Yb-doped fiber laser system at a repetition rate of $\ensuremath{\sim}$79 MHz via high harmonic generation in a Kr gas jet placed at the focus point of an external enhancement cavity. For Doppler-reduced spectroscopy, a collimated atomic beam of isotope-selected ${}^{132}\mathrm{Xe}$ is used as a target. Repeated measurements with different repetition frequencies and highly sensitive time-resolved detection allow us to determine the absolute transition frequency with an uncertainty of 140 MHz in the vuv region.