Strong Laser Fields
Department of Molecular and Optical Physics - University of Freiburg, Germany.
Threshold Photodetachment in a Repulsive Potential
A.O. Lindahl 1, J. Rohlén 1, H. Hultgren 1,2, I.Yu. Kiyan 2, D.J. Pegg 3, C.W. Walter 4, and D. Hanstorp 1
1 Department of Physics, University of Gothenburg, SE-412 96 Gothenburg, Sweden
2 Department of Molecular and Optical Physics, University of Freiburg, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany
3 Department of Physics, University of Tennessee, Knoxville, Tennessee 37996, USA
4 Department of Physics and Astronomy, Denison University, Granville, Ohio 43023, USA
Phys. Rev. Lett. 108, 033004 (2012) [5 pages]
We report on the first experimental observation of a new threshold behavior observed in the 5 2G partial channel in photodetachment of K-. It arises from the repulsive polarization interaction between the detached electron and the residual K(5 2G) atom, which has a large negative dipole polarizability. In order to account for the observation in the K(5 2G) channel, we have developed a semiclassical model that predicts an exponential energy dependence for the cross section. The measurements were made with collinear laser-ion beams and a resonance ionization detection scheme.
©2012 American Physical Society