Ytterbium atoms unlock quantum boost to 60-second magnetic coherence

Researchers affiliated with the Hefei National Research Center for Physical Sciences at the Microscale and the University of Science and Technology of China have achieved a spin coherence time of 60 seconds using ytterbium atoms, a duration that significantly exceeds typical cold-atom systems and promises more sensitive magnetic field sensors. The comagnetometer utilizes both isotopes of ytterbium, 171Yb (spin-1/2) and 173Yb (spin-5/2), jointly trapped within an optical lattice occupying approximately 160 lattice sites; vector and tensor light shifts are suppressed through polarization control and a Schrödinger cat state, respectively. This setup enables simultaneous Ramsey interferometry on both isotopes and achieves a magnetic noise suppression factor exceeding 3 x 10^4, while determining the ratio of nuclear magnetic moments to 4 parts per million precision. The results establish a new platform for spin-based sensing and may open pathways toward quantum-enhanced searches for physics beyond the Standard…