Determining the cause of this hesitation was also a challenge to the LAP theorists around Dr. Vladislav Yakovlev and his colleagues from the Vienna University of Technology (Austria) and the National Hellenic Research Foundation (Greece). Although they could confirm the effect qualitatively using complicated computations, they came up with a time offset of only five attoseconds. The cause of this discrepancy may lie in the complexity of the neon atom, which consists, in addition to the nucleus, of ten electrons. "The computational effort required to model such a many-electron system exceeds the computational capacity of today's supercomputers," explains Yakovlev.
Nevertheless, these investigations already point toward a probable cause of the "hesitation" of the electrons: the electrons interact not only with their atomic nucleus, but they are also influenced by one another. "This electron-electron interaction may then mean that it takes a short while before an electron that is shaken by the incident light wave is released by its fellow electrons and allowed to leave the atom," sais Dr. Martin Schulze, Postdoc at the LAP-Team.
"These to-date poorly understood interactions have a fundamental influence on electron movements in tiniest dimensions, which determine the course of all biological and chemical processes, not to mention the speed of microprocessors, which lie at the heart of computers", explains Ferenc Krausz. "Our investigations shed light on the electrons' interactions with one another on atomic scale". To this end, the fastest measuring technique in the world is just about good enough: the observed 20-attosecond time offset in
|Contact: Dr. Andreas Battenberg|
Technische Universitaet Muenchen