Autoionization state, laser spectroscopy

Recently, Bekov, Letokhov, Matveev and Mishin ) reported the observation of an autoionization state in gadolinium with the relatively long lifetime of 5 x 10 - s. The autoionization spectrum they observed by three-step laser spectroscopy is shown in Fig. 15. For isolated atoms, the width of the autoionization resonance is determined by its lifetime, so the 0.07 cm l half-width yields the estimated 0.5 ns lifetime. 

Laser spectroscopy methods substantially widen the scope of research into very narrow autoionization states. This can be illustrated by the long-lived autoionization state of the Gd atom (Bekov et al. 1978). Its lifetime is about 0.5ns, and Fa.i. 0.05 cm. A simplified energy-level diagram of gadolinium is shown in Fig. 9.4(a). The dye laser with Ai = 5618A used in the first excitation step raises gadolinium atoms from... 

Electron dynamics of photoionization states in the course of nonadiabatic transition is one of the important molecular processes. It can be applied to the studies on the following dynamical processes Tracking the history of electronic and vibrational states wandering among the excited states in laser fields with designed optical pulses. These time-dependent transient states should be able to be monitored in terms of time-resolved photoelectron spectroscopy [14, 353]. Inner shell ionization from a deep core level and the concomitant electronic state avalanches (decay) towards the hole, which may be accompanied by autoionization, is also quite interesting. In a... 

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