Tunnel ionization of K and Xe atoms by an intense CO₂ laser

Abstract

The energy spectra of electrons emitted radially from a CO 2 laser focus originating from the ionization of K and Xe atoms of tenuous gas pressure are measured. We simultaneously measured the cases in which medium laser intensities and high laser intensities are applied, fitting the ADK tunneling theory.

The tunnel ionization of atoms, diatomic and triatomic molecules using intense 10.6 mu m radiation

“…This theory (i.e. quasistatic tunnelling) has previously been successfully used (Xiong and Chin 1991, Corkum eta/ 1989, Augst eta1 1991 to describe the tunnelling behaviour in atoms, however, in this paper, its scope of validity has been extended into the realm of non-resonant simple molecules (i.e. diatomic and triatomic).…”

“…That is to say that no intermediate levels enter into the picture between the initial state of the atomic system and the final state in the continuum in this quasi-static tunnel ionization model. The scope of the concordance between this model and experiment has been tested through electron spectra (Corkum etaf 1989, Xiong and Chin 1991. ion yields for both singly Chin 1991, 1992) and multiply charged ions (Augst et a1 1991, Auguste et a1 1992) and using a variety of different laser characteristics (e.g.…”

“…A wide variety of experiments have studied the tunnel ionization of atoms under various aspects (e.g. Chin er al 1988, Augst et al 1989, 1991, Corkum el al 1989, Xiong and Chin 1991, Auguste et al 1992, Ilkov et al 1992, Mevel et al 1993. A number of theoretical discussions have also been presented over the past years (e.g.…”

“…ion yields for both singly Chin 1991, 1992) and multiply charged ions (Augst et a1 1991, Auguste et a1 1992) and using a variety of different laser characteristics (e.g. wavelength, pulse duration, polarization and intensity (Corkum et ai 1989, Xiong and Chin 1991, Auguste et ai 1992, nkov et a1 1992).…”

Improved treatment of the turning point in tunnel ionization of atoms in a low-frequency two color laser field

“…There are several analytical tunneling models [2,3]. One of the most used, the Amosov-Delone-Krainov (ADK), gives good agreement with the time dependent Schrodinger equa tion [4,5] and excellent agreement with experimental results [6]. This model for a linearly polarized laser field and the non zero initial momentum, p, of ejected photoelectrons describes the transition ionization rate as an exponential dependence on the field strength, F, the ionization potential of state, E i , the effective principle quantum number, n * [7]:…”