AI Insight
Researchers in Japan directly measured the ultrafast decay of an inner-shell vacancy (4d core hole) in xenon atoms using pairs of phase-coherent extreme ultraviolet light pulses from a synchrotron. By observing how interference patterns between photoelectron wave packets degraded as the time delay between pulses increased, they confirmed the core hole decays within approximately 6 femtoseconds. This time-domain measurement validated theoretical lifetime predictions using an innovative interferometric technique.
Why it matters
This work demonstrates a powerful method for directly measuring extremely short-lived atomic states in the time domain, which could advance our understanding of fundamental electron dynamics in atoms and molecules. The technique may find applications in studying ultrafast processes in chemical reactions and materials science where inner-shell vacancies play important roles.
Understand the Science
Researchers at the UVSOR Synchrotron Facility (Institute for Molecular Science, Japan) and partner institutions have observed the decay of a xenon 4d core hole, an inner-shell vacancy, directly in the time domain. They used pairs of phase-coherent extreme ultraviolet pulses from a synchrotron to make the photoelectron wave packets they released interfere. The contrast of the interference fringes decreased over a few femtoseconds as the delay between the pulses increased. A model using literature core-hole lifetimes of about 6 femtoseconds reproduced this rapid decay of the fringe contrast. The study is published in the journal Physical Review A.
Source: Light-pulse pairs reveal the femtosecond decay of an inner-shell hole in xenon atoms