Einstein's theory of general relativity states that clocks at different gravitational potentials tick
at different rates relative to lab coordinates—an effect known as the gravitational redshift. As …

We report an optical lattice clock with a total systematic uncertainty of 8.1× 10-19 in fractional
frequency units, representing the lowest uncertainty of any clock to date. The clock relies on …

Atomic clocks are vital in a wide array of technologies and experiments, including tests of
fundamental physics. Clocks operating at optical frequencies have now demonstrated …

Quantum entanglement has been generated and verified in cold-atom experiments and
used to make atom-interferometric measurements below the shot-noise limit. However …

Atomic frequency standards are used to generate accurate and precise time and frequency,
enabling many communications, synchronization, and navigation systems in modern life …

Building scalable quantum systems that demonstrate performance enhancement based on
entanglement is a major goal in quantum computing and metrology. The main challenge …

Rapid progress in optical atomic clock performance has advanced the frontiers of
timekeeping, metrology and quantum science,–. Despite considerable efforts, the …

The generation of long-lived entanglement in optical atomic clocks is one of the main goals
of quantum metrology. Arrays of neutral atoms, where Rydberg-based interactions may …

Linear quantum measurements with independent particles are bounded by the standard
quantum limit, which limits the precision achievable in estimating unknown phase …

State-of-the-art atomic clocks are based on the precise detection of the energy difference
between two atomic levels, which is measured in terms of the quantum phase accumulated …