Probing Matter with Attosecond Photo-Electron Wavepackets
Electronic processes and electron-driven reactions in atoms, molecules and condensed systems can proceed very rapidly, with relevant time-scales in the attosecond (1 attosecond=10-18 s) regime. When activated by the photoabsorption of extreme-ultra-violet attosecond laser pulses, the electron dynamics can be probed in real time by employing the coherent optical field of an additional infrared laser to mark time during the system’s evolution. While temporal resolutions on the order of 10 attoseconds have been demonstrated in such measurements, the physical insight which can be directly gleaned from these experiments has been limited, relying on extensive numerical simulations for interpretation. Now, a team from the University of Virginia and the Ohio State University has demonstrated a new technique that utilizes quantum interference in attosecond photoionization to directly reveal explicit information on an electron’s local environment, captured within a brief time interval (~ 1 femtosecond) following its emission. Initially applied to investigate the effects of electron correlation within atoms, the method should be applicable to molecules, and perhaps condensed systems as well.
D. Kiesewetter1 , R. R. Jones2, A. Camper1, S. B. Schoun1, P. Agostini1, and L. F. DiMauro1, “Probing Electronic Binding Potentials with Attosecond Photoelectron Wavepackets,” Nature Physics, doi: 10.1038/nphys4279 (October 2017).
1Department of Physics, The Ohio State University, Columbus, OH
2Department of Physics, University of Virginia, Charlottesville, VA
See full paper at http://dx.doi.org/10.1038/nphys4279
For a nice UVAToday write-up, see https://www.news.virginia.edu/content/physicists-take-snapshots-electrons-move