New lutetium atomic clock sets record for world's most accurate

Singapore's Centre for Quantum Technologies has built a lutetium-based atomic clock with a systematic uncertainty of 1.2×10⁻¹⁹, beating the 4.4×10⁻¹⁹ achieved with calcium ions earlier this year. Lutetium is less sensitive to thermal radiation and magnetic fields, and its frequency is about 10,000 times that of cesium.

• Systematic uncertainty of the lutetium clock is 1.2×10⁻¹⁹
• Previous record with calcium ions was 4.4×10⁻¹⁹
• Lutetium frequency is about 10,000 times that of cesium
• Lutetium is the rarest of Earth's rare earth elements