We report on the observation of the highly forbidden ^1S0–^3P0 optical clock transition in laser-cooled ^199Hg atoms.More than 95% depletion of cold ^199Hg atoms is detected in the magneto-optical trap. Using the fre...We report on the observation of the highly forbidden ^1S0–^3P0 optical clock transition in laser-cooled ^199Hg atoms.More than 95% depletion of cold ^199Hg atoms is detected in the magneto-optical trap. Using the free-of-field detection method, the AC Stark shift from the cooling laser is removed from the in-field spectroscopy. At low-power clock laser pumping, the linewidth of the clock spectroscopy is approximately 450 k Hz(full width at half-maximum), which corresponds to a Doppler broadening at the atom temperature of 60 μK. We determine the -1S0–^13P0transition frequency to be 1,128,575,290.819(14) MHz by referencing with a hydrogen maser and measuring with a fiber optical frequency comb. Moreover, a weak Doppler-free signal is observed.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(No.91436105)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB21030200)
文摘We report on the observation of the highly forbidden ^1S0–^3P0 optical clock transition in laser-cooled ^199Hg atoms.More than 95% depletion of cold ^199Hg atoms is detected in the magneto-optical trap. Using the free-of-field detection method, the AC Stark shift from the cooling laser is removed from the in-field spectroscopy. At low-power clock laser pumping, the linewidth of the clock spectroscopy is approximately 450 k Hz(full width at half-maximum), which corresponds to a Doppler broadening at the atom temperature of 60 μK. We determine the -1S0–^13P0transition frequency to be 1,128,575,290.819(14) MHz by referencing with a hydrogen maser and measuring with a fiber optical frequency comb. Moreover, a weak Doppler-free signal is observed.