Combining fiber Brillouin amplification with a repeater laser station for fiber-based optical frequency dissemination over 1400 km

Abstract

We investigate optical frequency dissemination over a 1400 km long fiber link in looped configuration over a pair of underground fibers between Braunschweig and Strasbourg. This fiber link is the first to combine fiber Brillouin amplifiers with a repeater laser station. Phase-coherent operation over more than five days is demonstrated. We analyze the repeatability of the performance over four campaigns and present results of 65 days in total. The weighted mean of the fractional frequency offset of the transferred optical frequency over the complete data set is $(-1.1\pm 0.4)\times 10^{-20}$. By analyzing the stabilization signals of the two individual fibers, the correlation of the phase noise on the two fibers is shown to be >98%.

12 pages, 6 figures

References in corpus (26)

• Frequency Comparison of Two High-Accuracy Al+ Optical Clocks
• Systematic evaluation of an atomic clock at 2e-18 total uncertainty
• Single-Ion Atomic Clock with $3\times 10^{-18}$ Systematic Uncertainty
• Geodesy and metrology with a transportable optical clock
• Optical clock intercomparison with $6\times 10^{-19}$ precision in one hour
• A clock network for geodesy and fundamental science
• Real-time geopotentiometry with synchronously linked optical lattice clocks
• A transportable optical lattice clock with $7\times 10^{-17}$ uncertainty
• Test of special relativity using a fiber network of optical clocks
• Coherent optical frequency transfer at 5e-19 over a doubled 642 km fiber link
• Long-distance frequency transfer over an urban fiber link using optical phase stabilization
• Cascaded multiplexed optical link on a telecommunication network for frequency dissemination
• Coherent optical phase transfer over a 32-km fiber with 1-s instability at $10^{-17}$
• On the measurement of frequency and of its sample variance with high-resolution counters
• Brillouin amplification in phase coherent transfer of optical frequencies over 480 km fiber
• Brillouin amplification supports $1\times 10^{-20}$ accuracy in optical frequency transfer over 1400~km of underground fibre
• Cascaded optical fiber link using the Internet network for remote clocks comparison
• A transportable 40Ca+ single-ion clock with $7.7\times 10^{-17}$ systematic uncertainty
• First international comparison of fountain primary frequency standards via a long distance optical fiber link
• Comparing optical oscillators across the air to milliradians in phase and $10^{-17}$ in frequency
• On the relation between uncertainties of weighted frequency averages and the various types of Allan deviations
• First industrial-grade coherent fiber link for optical frequency standard dissemination
• Optical frequency transfer via a 660 km underground fiber link using a remote Brillouin amplifier
• Characterization of a 450-km Baseline GPS Carrier-Phase Link using an Optical Fiber Link
• Distributed Raman optical amplification in phase coherent transfer of optical frequencies
• Two-Branch Fiber Link for International Clock Networks

Cited by in corpus (6)

• Ultralight Dark Matter Search with Space-Time Separated Atomic Clocks and Cavities
• Coordinated international comparisons between optical clocks connected via fiber and satellite links
• Universal formalism for data sharing and processing in clock comparison networks
• E-21 Level Instability Frequency Dissemination over 2067 km noisy Telecommunication Infrastructure
• Potentials for general-relativistic geodesy
• General Relativity and Geodesy