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Updated: Jul 7, 2026
09:38
Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
Physics of systematic frequency variations in hydrogen masers
1Smithsonian Astrophys. Obs., Cambridge, MA.
Summary
Hydrogen maser frequency stability beyond 10^4 seconds is limited by systematic effects. Cavity pulling and wall shift variations are key internal mechanisms impacting long-term performance.
Area of Science:
- Atomic physics
- Metrology
- Quantum electronics
Background:
- Hydrogen masers are critical for precise timekeeping.
- Long-term frequency stability is limited by systematic effects.
Purpose of the Study:
- Investigate internal physics limiting hydrogen maser frequency stability.
- Identify key systematic effects and their magnitudes.
- Propose strategies for improvement.
Main Methods:
- Analysis of frequency-determining mechanisms.
- Estimation of systematic effect magnitudes.
- Discussion of environmental factor influences.
Main Results:
- Cavity pulling limits stability to ~10^-15 per day.
- Wall shift variations impact stability between 10^-16 and 10^-15 per day.
- Internal maser physics and external factors are interconnected.
Conclusions:
- Cavity pulling and wall shift variations are primary limitations.
- Strategies exist to mitigate systematic frequency variations.
- Further research can enhance long-term maser stability.
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