Freie Universit?t Berlin, Institut für Physikalische und Theoretische Chemie, Takustr. 3, 14195 Berlin, Germany, DE
Abstract:
We have studied the ionization of Rydberg-excited xenon atoms in THz-laser fields and by quantum dynamical calculations. The
experimental threshold laser field strength for 10% ionization probability follows an n*-1.68 (1.04 THz) dependence (n* effective principal quantum number) with additional weak resonance structures and shows that ionization does not occur by
a Landau-Zener mechanism. At scaled frequencies of to 5.6 the simulated threshold fields for ionization in oscillatory fields show a dependence on the principal quantum number
n of n-4.1 to n-1.35.
Received: 17 February 1998 / Revised: 20 April 1998 / Accepted: 21 April 1998