A clock network for geodesy and fundamental science

Abstract

Leveraging the unrivaled performance of optical clocks in applications in fundamental physics beyond the standard model, in geo-sciences, and in astronomy requires comparing the frequency of distant optical clocks truthfully. Meeting this requirement, we report on the first comparison and agreement of fully independent optical clocks separated by 700 km being only limited by the uncertainties of the clocks themselves. This is achieved by a phase-coherent optical frequency transfer via a 1415 km long telecom fiber link that enables substantially better precision than classical means of frequency transfer. The fractional precision in comparing the optical clocks of three parts in $10^{17}$ was reached after only 1000 s averaging time, which is already 10 times better and more than four orders of magnitude faster than with any other existing frequency transfer method. The capability of performing high resolution international clock comparisons paves the way for a redefinition of the unit of time and an all-optical dissemination of the SI-second.

14 pages, 3 figures, 1 table

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Cited by in corpus (123)

• 20 years of developments in optical frequency comb technology and applications
• Geodesy and metrology with a transportable optical clock
• Ultra-stable optical clock with two cold-atom ensembles
• Entanglement-Enhanced Optical Atomic Clock
• Atomic Clocks for Geodesy
• 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
• A high-performance optical lattice clock based on bosonic atoms
• Detecting dark matter waves with precision measurement tools
• Coherent phase transfer for real-world twin-field quantum key distribution
• Roadmap towards the redefinition of the second
• 113 km Free-Space Time-Frequency Dissemination at the 19th Decimal Instability
• Quantum sensing with atomic, molecular, and optical platforms for fundamental physics
• Operational Magic Intensity for Sr Optical Lattice Clocks
• Quantum key distribution over 658 km fiber with distributed vibration sensing
• Frequency measurements of superradiance from the strontium clock transition
• Quantum-limited optical time transfer for future geosynchronous links
• Femtosecond Synchronization of Optical Clocks Off of a Flying Quadcopter
• A transportable 40Ca+ single-ion clock with $7.7\times 10^{-17}$ systematic uncertainty
• Continuous Bose-Einstein condensation
• First international comparison of fountain primary frequency standards via a long distance optical fiber link
• Point-to-Point Stabilised Optical Frequency Transfer with Active Optics
• Comparing a mercury optical lattice clock with microwave and optical frequency standards
• Comparing optical oscillators across the air to milliradians in phase and $10^{-17}$ in frequency
• Determination of a high spatial resolution geopotential model using atomic clock comparisons
• Heisenberg-limited noisy atomic clock using a hybrid coherent and squeezed states protocol
• Lattice-induced photon scattering in an optical lattice clock
• Absolute frequency measurement of the 1S0 - 3P0 transition of 171Yb
• Femtosecond Optical Two-Way Time-Frequency Transfer in the Presence of Motion
• Towards a Transportable Aluminium Ion Quantum Logic Optical Clock
• First industrial-grade coherent fiber link for optical frequency standard dissemination
• Optical frequency ratio of a ${}^{171}{\mathrm{Yb}}^{+}$ single-ion clock and a ${}^{87}\mathrm{Sr}$ lattice clock
• GENESIS: Co-location of Geodetic Techniques in Space
• A noise-immune cavity-assisted non-destructive detection for an optical lattice clock in the quantum regime
• The unit of time: present and future directions
• Inertial quantum sensors using light and matter
• A strontium optical lattice clock with $1\times 10^{-17}$ uncertainty and measurement of its absolute frequency
• Optically synchronized fiber links with spectrally pure integrated lasers
• Stabilized microwave-frequency transfer using optical phase sensing and actuation
• Optical frequency divider with division uncertainty at the 10^(-21) level
• Stabilized free-space optical frequency transfer
• The Companion of Enrico's Chart for Phase Noise and Two-Sample Variances
• Single-ion, transportable optical atomic clocks
• Direct comparisons of European primary and secondary frequency standards via satellite techniques
• On-Line Estimation of Local Oscillator Noise and Optimisation of Servo Parameters in Atomic Clocks
• Hybrid fiber links for accurate optical frequency comparisons
• Time shifting deviation method enhanced laser interferometry: ultrahigh precision localizing of traffic vibration using urban fiber link
• SI-traceable frequency dissemination at 1572.06 nm in a stabilized fiber network with ring topology
• Probing Time Dilation in Coulomb Crystals in a high-precision Ion Trap
• All-polarization-maintaining, single-port Er:fiber comb for high-stability comparison of optical lattice clocks
• A terahertz vibrational molecular clock with systematic uncertainty at the $10^{-14}$ level
• Entanglement-Enhanced Optical Atomic Clocks
• Experimental and theoretical investigation of a multi-mode cooling scheme using multiple EIT resonances
• Combining fiber Brillouin amplification with a repeater laser station for fiber-based optical frequency dissemination over 1400 km
• Long-distance chronometric leveling with a portable optical clock
• Passive Optical Phase Noise Cancellation
• Ab initio quantum theory of mass defect and time dilation in trapped-ion optical clocks
• Robust optical clock transitions in trapped ions
• Optical Atomic Clock Comparison through Turbulent Air
• Chronometric geodesy: methods and applications
• Reduction of light shifts in Ramsey spectroscopy with a combined error signal
• Observation of an Inner-Shell Orbital Clock Transition in Neutral Ytterbium Atoms
• Quadrupole shift cancellation using dynamic decoupling
• Ultralight Dark Matter Search with Space-Time Separated Atomic Clocks and Cavities
• Dual-comb-enhanced microwave clock synchronization over commercial fiber
• Absolute frequency measurement of the 87Sr optical lattice clock at NTSC using International Atomic Time
• Improved Frequency Ratio Measurement with 87Sr and 171Yb Optical Lattice Clocks at NMIJ
• Methods for coherent optical Doppler orbitography
• Coordinated international comparisons between optical clocks connected via fiber and satellite links
• Intensity interferometry for ultralight bosonic dark matter detection
• Branching optical frequency transfer with enhanced post automatic phase noise cancellation
• Time-Frequency Transfer over Optical Fiber
• A universal, plug-and-play synchronisation scheme for practical quantum networks
• Multi-node optical frequency dissemination with post automatic phase correction
• Two-Branch Fiber Link for International Clock Networks
• Incubating Advances in Integrated Photonics with Emerging Sensing and Computational Capabilities
• Improving Short-Term Stability in Optical Lattice Clocks by Quantum Nondemolition Measurements
• Simple Stabilized Radio-Frequency Transfer with Optical Phase Actuation
• Offset-locking-based frequency stabilization of external cavity diode lasers for long-distance quantum communication
• GHZ protocols enhance frequency metrology despite spontaneous decay
• The Relativistic Geoid: Gravity Potential and Relativistic Effects
• Digital Doppler-cancellation servo for ultra-stable optical frequency dissemination over fiber
• Synchronous multi-color laser network with daily sub-femtosecond timing drift
• Demonstration of chronometric leveling using transportable optical clocks beyond laser coherence limit
• Fully digital platform for local ultra-stable optical frequency distribution
• Real-time free-running time scale with remote clocks on fiber-based frequency network
• Universal formalism for data sharing and processing in clock comparison networks
• Phase noise cancellation in polarisation-maintaining fibre links
• Hundred-Femtosecond-Level Concise Optical Time Delay Measurement System Based on Linear Optical Sampling
• Lunar Laser Ranging with High-Power CW Lasers
• Potential and scientific requirements of optical clock networks for validating satellite gravity missions
• Open-Loop Polarization Mode Dispersion Mitigation for Fibre-Optic Time and Frequency Transfer
• Access via laboratory experiments to the level mixing effect induced by blackbody radiation and its influence on the cosmological hydrogen recombination problem
• Studies of thorium and ytterbium ion trap loading from laser ablation for gravity monitoring with nuclear clocks
• Node-downloadable frequency transfer system based on a mode-locked laser with over 100 km of fiber
• Wavefront Curvature in Optical Atomic Beam Clocks
• Ratchet Loading and Multi-Ensemble Operation in an Optical Lattice Clock
• Search for transient variations of the fine structure constant and dark matter using fiber-linked optical atomic clocks
• Optical ultra-stable optical clock cavities as resonant mass gravitational wave detectors in search for new physics
• Entanglement-enhanced Synchronous differential comparison
• Direct Phase Locking of a Ti:Sapphire Optical Frequency Comb to a Remote Optical Frequency Standard
• Orders-of-magnitude improvement in precision spectroscopy of an inner-shell orbital clock transition in neutral ytterbium
• Quantum Sensing Using Atomic Clocks for Nuclear and Particle Physics
• Temperature-dependent mechanical losses of Eu${}^{3+}$:Y${}_2$SiO${}_5$ for spectral hole burning laser stabilization
• Cold Atoms in Space: Community Workshop Summary and Proposed Road-Map
• Fundamental Limitations of Rayleigh Backscattering Noise on Fiber-Based Multiple-Access Optical Frequency Transfer
• Photoionization cross sections of ultracold ${}^{88}$Sr in ${}^1$P${}_1$ and ${}^3$S${}_1$ states at 390 nm and the resulting blue-detuned magic wavelength optical lattice clock constraints
• Free space optical link to a tethered balloon for frequency transfer
• Extended gravitational clock compass: new exact solutions and simulations
• High-precision Time-Frequency Signal Simultaneous Transfer System via a WDM-based Fiber Link
• International Optical Clock Comparison Using the European Optical Fiber Network
• E-21 Level Instability Frequency Dissemination over 2067 km noisy Telecommunication Infrastructure
• A High-frequency Geodetic VLBI Experiment for Optical Clock Comparison
• The permanent tide and the International Height Reference Frame IHRF
• Bayesian Frequency Metrology with Optimal Ramsey Interferometry in Optical Atomic Clocks
• Seismology with optical links: enabling a global network for submarine earthquake monitoring
• Extraordinary low systematic frequency shifts in bi-colour thulium optical clock
• Enhanced timing of a 113 km O-TWTFT link with digital maximum likelihood estimation process
• Unification of global height system at centimeter level using precise frequency signal links
• Preliminary experimental results of determining the geopotential difference between two synchronized portable hydrogen clocks at different locations
• Determining geopotential difference via relativistic precise point positioning time comparison: A case study using simulated observations
• Dual optical frequency combs with ultra-low relative phase jitters from 550 nm to 1020 nm for precision spectroscopy