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Research project Timing many-body effects in small quantum systems

When atomic systems are exposed to light it is the electrons that react first. They absorb the radiation and convert the photon energy into excitation and ionization. Ultra-short light pulses are tools to study this dynamics in real time.

Illustration Marcus Isinger
Artistic illustration of how a train of attosecond pulses (blue) and a IR-laser pulse (red) interact with electrons in the two outer shells of Neon.

The goal of attosecond science is to understand, and ultimately control, electron dynamics on its natural time-scale. One
most interesting sequence of events follows the creation of a so-called core-hole in an inner shell of the atom. The sudden
removal of an electron initiates screening and relaxation processes through the subtle interplay between the remaining
electrons. With ultra-short light pulses the creation of the core hole can be clocked precisely and the onset of the events that
follow can be studied as a function of time.  We work with theory and  calculations to extract key information from
experiments and to deepen our understanding of electron dynamics.

Project description

Extremely short bursts of coherent light are today routinely generated in many laser laboratories around the world. The
shortness of these bursts, typically  around hundred attoseconds (1 as = 10^(-18) s), has enabled time-domain studies of  
electronic processes.   Although the fantasy image of  a camera  fast enough to film  the  motion of the electrons is too
naive, it still describes  the essence of attosecond science to some extent. We build  theoretical and computational tools for
the interpretation and quantitative description of  experimental observations with attosecond light sources. It is precisely
because the snap-shot camera idea  is too simplified, that our focus is on  how  timing information can be obtained, and how
it should be interpreted.

Project members

Project managers

Eva Lindroth


Department of Physics
Eva Lindroth


Soumyajit Saha


Department of Physics

Johanna Sörngård


Department of Physics
Profile picture focusing on face. Johanna is standing outside.

Anton Ljungdahl


Department of Physics