Ytterbium ion holds a quantum state for tens of seconds

Physicists measured long-lived states in a trapped ytterbium ion, a step for atomic clocks and quantum memory.

Researchers from the University of Amsterdam and the University of New South Wales measured a set of long-lived metastable states in a single ytterbium ion (Yb+). Working in the lab of Rene Gerritsma at the UvA Institute of Physics, the team laser-excited one ion to a high energy level and watched it decay through lower states. They recorded lifetimes of roughly 1 second and 10 seconds, and found evidence for a state lasting longer than 30 seconds. The work, first-authored by Zeger Ackerman, was published in Physical Review A in 2026.

The experiment trapped two ions together: one for spectroscopy and one to continuously cool the system. The 'dark' metastable ion gives itself away by pushing its fluorescing partner off-centre in the trap. Detailed atomic structure calculations backed the measurements. The 1-second state, reachable from the ground state with a single laser pulse, also settles a 35-year-old prediction by Fawcett and Wilson, who had estimated 5.2 seconds — close, but not exact.

Why it matters for abundance: trapped ions sit at the heart of atomic clocks and quantum computers. States that stay stable for seconds are attractive for holding qubit information and for the precision timekeeping that underpins navigation and measurement. Better tools here eventually feed into knowledge infrastructure and sensing that touches health.

The caveats are real. The lifetime above 30 seconds is 'evidence for,' not a precise measurement, and the applications remain prospective, resting on calculations rather than working devices. The source carries the full technical detail.

Source: Phys.org