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Optical-Clock-Based Time Scale.

Jian Yao1, Jeff A Sherman1, Tara Fortier1

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This summary is machine-generated.

A new hybrid time scale combines intermittent optical clocks with continuous microwave clocks. This innovation achieves unprecedented sub-nanosecond accuracy and improved frequency stability for precise timekeeping.

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Area of Science:

  • Metrology
  • Atomic Physics
  • Navigation Systems

Background:

  • Current time scales rely on microwave atomic clocks for accuracy and reliability.
  • Emerging optical clocks offer superior stability but lack continuous operation capabilities.
  • Integrating intermittent optical clocks into time scales presents significant challenges.

Purpose of the Study:

  • To develop a novel hybrid time scale architecture integrating microwave and optical atomic clocks.
  • To overcome the limitations of continuous operation for optical clocks in timekeeping.
  • To enhance the accuracy and stability of time scales beyond current capabilities.

Main Methods:

  • Development of a hybrid time scale system utilizing an ensemble of microwave atomic clocks as a flywheel oscillator.
  • Intermittent operation of highly stable optical clocks, synchronized with the microwave ensemble.
  • Characterization of the time scale's accuracy and frequency stability against Coordinated Universal Time (UTC).

Main Results:

  • Demonstrated sub-nanosecond accuracy over several months.
  • Achieved a fractional frequency stability of 1.45 × 10-16 at 30 days, reaching the 10-17 decade at 50 days.
  • The hybrid approach leverages the Dick-effect limit for improved performance.

Conclusions:

  • The developed hybrid microwave-optical time scale offers a significant advancement in timekeeping accuracy and stability.
  • This new architecture addresses the operational limitations of optical clocks, paving the way for their practical application.
  • The findings could lead to a paradigm shift in the design and implementation of future time-scale systems.