Atomic clock with 1×10(-18) room-temperature blackbody Stark uncertainty

Area of Science:

• Atomic physics
• Metrology
• Quantum optics

Background:

• Blackbody radiation (BBR) poses a significant challenge to the precision of atomic frequency standards.
• Precisely characterizing the BBR environment within atomic clock apparatus is difficult.
• The Stark shift induced by BBR is a primary limitation in atomic clock performance.

Purpose of the Study:

• To develop and demonstrate an in-vacuum radiation shield for a well-characterized BBR environment.
• To reduce the uncertainty associated with the BBR Stark shift in atomic clocks.
• To enable precise measurement of BBR shift temperature dependence.

Main Methods:

• An in-vacuum radiation shield was designed and implemented for an ytterbium optical lattice clock.
• The shield was operated at room temperature and elevated temperatures to assess BBR environment.
• Fractional clock uncertainty contributions from BBR were precisely specified.

Main Results:

• The shield provided a uniform and well-characterized BBR environment at room temperature.
• The BBR environment specification yielded a fractional clock uncertainty of 5.5×10⁻¹⁹.
• Total uncertainty for the BBR Stark shift was reduced to 1×10⁻¹⁸.
• Operation at elevated temperatures confirmed BBR shift temperature dependence and environmental evaluation consistency.

Conclusions:

• The developed in-vacuum radiation shield significantly enhances the precision of atomic clocks.
• This technology offers a pathway to more accurate atomic frequency standards by controlling BBR effects.
• The shield's ability to measure temperature dependence validates its environmental characterization capabilities.