Strong-field ionization in time-dependent density functional theory

¹  Max-Planck-Institut für Physik komplexer Systeme - Nöthnitzer Strasse 38, D-01187 Dresden, Germany, EU
²  Institut für Physik, Universität Kassel - D-34132 Kassel, Germany, EU
³  Physikalisches Institut, Universität Bayreuth - D-95440 Bayreuth, Germany, EU

Received: 18 July 2008
Accepted: 9 October 2008

Abstract

Ionization in a strong laser field is a prime example of non-perturbative, correlated electron dynamics. Simulating such processes on a first-principles basis is a major theoretical challenge. We demonstrate that time-dependent density functional theory (TDDFT) on the basis of a newly developed functional for the correlation potential incorporates the relevant electron interaction effects. The central idea of our approach is to exploit information about exact ground-state correlation in approximate time-dependent calculations. The new functional provides an accurate description of the paradigm problem of the double ionization of the Helium atom, showing that TDDFT is a viable tool for strong-field calculations.