Heidelberg 2015 – wissenschaftliches Programm
A 32.2: Vortrag
Donnerstag, 26. März 2015, 15:00–15:15, C/HSW
Inversion symmetry breaking of atomic bound states in strong laser fields — •Veit Stooß1, Andreas Kaldun1, Alexander Blättermann1, Thomas Ding1, Christian Ott2, and Thomas Pfeifer1 — 1Max Planck Institut für Kernphysik, Heidelberg, Deutschland — 2University of California, Berkeley, USA
Light induced states represent one of the most prominent features appearing in transient-absorption spectroscopy and contain a lot of information about dynamic processes. Disentangling and understanding the various contributions to these features is essential in order to gain information about the induced couplings and electronic dynamics of atomic and molecular systems in strong external fields. We present an explanation for the physical origin of spectral features arising at one photon energy around dipole-forbidden states in transient-absorption spectra. The results are based on experiments in singly-excited Helium and a few-level model calculation. The features appear due to instantaneous polarization and breaking of the symmetry of the atom following the infrared-fs pulse used in the transient-absorption scheme. Using this effect the onset of symmetry-breaking for low-lying states in Helium by tuning from a weak to a strong electric field was directly observed.