Tag: #metrology

Thorium‑229 Nuclear Clocks Demonstrated in Vienna and Beijing; Vienna Shows First Self‑Stabilizing Prototype

Teams in Vienna and Beijing report operational thorium‑229 nuclear clocks; Vienna's device is the first self‑stabilizing prototype, running >24 hours.

#nuclearclock, #thorium229, #metrology, #precision

Two Independent Teams Demonstrate Operational Thorium-229 Nuclear Clocks

Two independent teams report operational thorium-229 nuclear clocks, locking lasers to a nuclear transition and advancing compact, reproducible nuclear timekeeping.

#nuclearclock, #thorium229, #metrology, #precision

PTB reports interspecies optical‑clock comparison below 5×10⁻¹⁸ using transportable clock

PTB reports a transportable strontium lattice clock matched a stationary ytterbium‑ion clock to 4.3×10⁻¹⁸ uncertainty; result is a preprint.

#physics, #opticalclocks, #metrology, #ptb

Boulder team reports optical clock comparisons hitting 3.2×10⁻¹⁸ uncertainty, a milestone toward redefining the second

Researchers in Boulder compared three optical atomic clocks with uncertainties down to 3.2×10⁻¹⁸, meeting a benchmark for redefining the SI second.

#opticalclocks, #metrology, #timekeeping, #atomicphysics