Dynamic decoupling of laser phase noise in compound atomic clocks

Abstract

The frequency stability achieved by an optical atomic clock ultimately depends on the coherence of its local oscillator. Even the best ultrastable lasers only allow interrogation times of a few seconds, at present. Here we present a universal measurement protocol that overcomes this limitation. Engineered dynamic decoupling of laser phase noise allows any optical atomic clock with high signal-to-noise ratio in a single interrogation to reconstruct the laser's phase well beyond its coherence limit. A compound clock is then formed in combination with another optical clock of any type, allowing the latter to achieve significantly higher frequency stability than on its own. We demonstrate implementation of the protocol in a realistic proof-of-principle experiment with a phase reconstruction fidelity of 99 %. The protocol enables minute-long interrogation for the best ultrastable laser systems. Likewise, it can improve clock performance where less stable local oscillators are used, such as in transortable systems.

arXiv comment14 pages, 4 figures

References in corpus (20)

• Dynamical Decoupling of Open Quantum Systems
• 1.5 $\mu$m lasers with sub 10 mHz linewidth
• Hunting for topological dark matter with atomic clocks
• Geodesy and metrology with a transportable optical clock
• Optical clock intercomparison with $6\times 10^{-19}$ precision in one hour
• Frequency ratio of two optical clock transitions in ${}^{171}$Yb${}^{+}$ and constraints on the time-variation of fundamental constants
• Gravitational wave detection with optical lattice atomic clocks
• Ultra-stable optical clock with two cold-atom ensembles
• Improved limit on a temporal variation of $m_p/m_e$ from comparisons of Yb${}^{+}$ and Cs atomic clocks
• Optical clock comparison test of Lorentz symmetry
• Test of special relativity using a fiber network of optical clocks
• First observation with global network of optical atomic clocks aimed for a dark matter detection
• Ultra-precise measurement of optical frequency ratios
• Enhanced effects of variation of the fundamental constants in laser interferometers and application to dark matter detection
• Noise and instability of an optical lattice clock
• Quantum coherence between two atoms beyond Q=10^15
• Delivering pulsed and phase stable light to atoms of an optical clock
• Probing beyond the laser coherence time in optical clock comparisons
• Searching for topological defect dark matter with optical atomic clocks
• Search for transient variations of the fine structure constant and dark matter using fiber-linked optical atomic clocks