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Updated: Feb 9, 2026
10:17
20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier
Published on: July 12, 2017
12.0K
A Sub-ps Stability Time Transfer Method Based on Optical Modems.
Summary
This study presents a new method for transferring time using optical demodulation over an 86-km fiber link, achieving sub-picosecond resolution for precise optical clock comparisons.
Area of Science:
- Physics
- Metrology
- Optical Engineering
Background:
- Advanced optical clocks require stable time scales for comparison.
- Optical fiber links offer a potential solution for continental-scale clock synchronization.
- Existing methods for time transfer via fiber optics need further exploration and improvement.
Purpose of the Study:
- To investigate a novel method for time transfer using optical demodulation.
- To demonstrate the feasibility of this method over a long-distance urban fiber link.
- To assess the stability and resolution of the time transfer system.
Main Methods:
- Implementation of a proof-of-principle experiment utilizing phase step imprinting onto an optical carrier.
- Testing the system over an 86-km urban optical fiber.
- Measuring time interval transfer stability for a 1 pulse per second signal.
Main Results:
- Achieved sub-picosecond resolution for time interval transfer.
- Demonstrated stability from 10 seconds to one day of measurement time.
- Successful proof-of-principle experiment over 86-km urban fiber.
Conclusions:
- The developed optical demodulation method is effective for high-resolution time transfer.
- The technique shows promise for enhancing the stability of time scales and enabling comparisons of advanced optical clocks.
- Future work will focus on performance optimization and integration into active telecommunication networks.
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