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Exact field ionization rates in the barrier suppression-regime from numerical TDSE calculations

D. Bauer·P. Mulser
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Abstract

Numerically determined ionization rates for the field ionization of atomic hydrogen in strong and short laser pulses are presented. The laser pulse intensity reaches the so-called "barrier suppression ionization" regime where field ionization occurs within a few half laser cycles. Comparison of our numerical results with analytical theories frequently used shows poor agreement. An empirical formula for the "barrier suppression ionization"-rate is presented. This rate reproduces very well the course of the numerically determined ground state populations for laser pulses with different length, shape, amplitude, and frequency. Number(s): 32.80.Rm

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D. Bauer, P. Mulser. 1998-09-10. Exact field ionization rates in the barrier suppression-regime from numerical TDSE calculations. https://doi.org/10.1103/physreva.59.569

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