title: Absolute frequency measurement of rubidium 5S-7S two-photon transitions with a femtosecond laser comb.
abstract: The absolute frequencies of rubidium 5S-7S two-photon transitions at 760 nm are measured to an accuracy of 20 kHz with an optical frequency comb based on a mode-locked femtosecond Ti:sapphire laser. The rubidium 5S-7S two-photon transitions are potential candidates for frequency standards and serve as important optical frequency standards for telecommunication applications. The accuracy of the hyperfine constant of the 7S1/2 state is improved by a factor of 5 in comparison with previous results.
authors.affiliation: Department of Physics, National Tsing Hua University, Hsinchu 300, Taiwan. hcchui@itri.org.tw
authors.forename: Hsiang-Chen
authors.initials: HC
authors.lastname: Chui
authors.forename: Ming-Sheng
authors.initials: MS
authors.lastname: Ko
authors.forename: Yi-Wei
authors.initials: YW
authors.lastname: Liu
authors.forename: Jow-Tsong
authors.initials: JT
authors.lastname: Shy
authors.forename: Jin-Long
authors.initials: JL
authors.lastname: Peng
authors.forename: Hyeyoung
authors.initials: H
authors.lastname: Ahn