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Updated: Dec 25, 2025
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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
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Robust optical frequency dissemination with a dual-polarization coherent receiver
Optics Express
|April 1, 2020
Summary
This study introduces a new dual-polarization method to prevent signal fading in optical fiber frequency dissemination. The technique enhances the reliability of optical links for physics experiments requiring precise, long-term measurements.
Area of Science:
- Physics
- Optical Engineering
- Signal Processing
Background:
- Frequency dissemination via optical fiber links is crucial for precision measurements.
- Signal detection failures due to polarization-induced beatnote fading limit the reliability of these links.
Purpose of the Study:
- To develop a robust method for reliable frequency dissemination over optical fiber links.
- To overcome the limitations imposed by polarization changes on optical beatnote detection.
Main Methods:
- Implementation of a dual-polarization coherent receiver.
- Development of dedicated signal processing algorithms on a field-programmable gate array (FPGA).
- Theoretical and experimental analysis of polarization-induced phase noise.
Main Results:
- Successful mitigation of beatnote fading caused by polarization variations.
- Demonstration of endless tracking of optical phase.
- Quantification of polarization-induced phase noise.
Conclusions:
- The proposed dual-polarization method significantly enhances the reliability and robustness of optical fiber frequency dissemination.
- This advancement removes a key obstacle for physics experiments demanding long measurement times and high precision.
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