In this paper we report a direct observation of the oscillation between bound-state configurations in a rapidly autoionizing system. Calcium atoms were excited to a pure 4p3/2nd two-electron configuration using a 500-fsec laser pulse. The initial 4p3/2nd doubly excited state is energy degenerate with the 4p1/2n'd states and several continuum channels. Because of the short-pulse excitation, the initial state of the atom is not an energy eigenstate, but a nonstationary wave packet. As a result, oscillations between the two bound configurations were produced. These oscillations were measured by scanning the timing of a second 500-fsec laser pulse tuned to drive the 4p1/2n'd ionic state back down to the 4sn'd singly excited configuration, which was subsequently detected using selective field ionization. A simple theoretical model was used to model the experimental results and produced good agreement with the data.
H. N. Ereifej and J. G. Story, "Direct Measurement of Oscillations between Degenerate Two-Electron Bound-State Configurations in a Rapidly Autoionizing System," Physical Review A - Atomic, Molecular, and Optical Physics, vol. 62, no. 2, pp. 023404-1-023404-5, American Physical Society (APS), Jul 2000.
The definitive version is available at http://dx.doi.org/10.1103/PhysRevA.62.023404
Keywords and Phrases
Calcium; Dye lasers; Ground state; Laser pulses; Mathematical models; Photoionization; Quantum theory; Solid state lasers; Ultrafast phenomena; Excited state; Rydberg state; Self mode-locked laser; Titanium doped sapphire laser; Atomic physics
International Standard Serial Number (ISSN)
Article - Journal
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