Overview
- The team led by Gerald Gabrielse published the result in Physical Review Letters on Oct. 21, 2026, reporting that a single positron was held in a controlled quantum state for about a month.
- Researchers captured positrons from sodium-22 decay, slowed them through a cold tungsten crystal lattice, and funneled one into a wall-less electromagnetic trap cooled to roughly 0.3 kelvin in a near-perfect vacuum.
- Inside the trap the group created the first one-positron quantum cyclotron and demonstrated control of individual quantum transitions using tuned microwave pulses, allowing repeated, observable state changes.
- The immediate goal is a high-precision measurement of the positron's magnetic moment to compare directly with the electron; any confirmed difference would challenge CPT symmetry and could shed light on the matter–antimatter imbalance.
- Gabrielse's prior electron measurement reached about one part in 10 trillion, giving the new apparatus a precise benchmark and setting the stage for results that could either tighten limits on new physics or point to a major discrepancy.