ELFT HÍRADÓ

[<vera.horvath AT eli-alps.hu>]

Meghívó az ELI-ALPS szemináriumára

Előadó: Tőkési Károly
Cím:   Classical Trajectory Monte Carlo method  – „Watching quantum physics in
real time”

Időpont: 2016. február 12. 9 óra
Helyszín: Szeged, Tisza Lajos krt. 85-87.

Absztrakt: Attosecond physics is a new and rapidly developing field driven by
recent advances in laser technology. Attosecond science holds the promise to
observe and to control the motion of electrons on their natural time scale. It
is now possible to take snapshots of electrons in motion in atoms, molecules,
and solids. The long-lasting dream of chemists and physicists to watch and to
control in real time the formation and breaking of chemical bonds or electrons
leaving an atom is now closer to realization than ever. These experimental
advances pose considerable challenges for theory.

Time-resolved photoemission experiments employing attosecond streaking of
electrons emitted by an extended ultraviolet pump pulse and probed by a few-
cycle near-infrared pulse found a time delay of about 100 as between
photoelectrons from the conduction band and those from the 4f core level of
tungsten. We present a microscopic simulation of the emission time and energy
spectra employing a classical transport theory. Our calculations reproduced
well both the emission spectra and streaking images. We found delay times near
the lower bound of the experimental data.

Photoemission spectra feature also complex correlation satellite structures
signifying the simultaneous excitation of single or multiple plasmons. The
time delay of the plasmon satellites relative to the main line can be resolved
in attosecond streaking experiments. Time-resolved photoemission thus provides
the key to discriminate between intrinsic and extrinsic plasmon excitation. We
demonstrate the determination of the branching ratio between intrinsic and
extrinsic plasmon generation for simple metals.

A szeminárium angol nyelvű. Minden érdeklődőt szívesen látunk.