Time-dependent density-functional theory with optimized effective potential and self-interaction correction: Application to the study of coherent control of multiple high-order harmonic generation of He atoms in mixed laser fields

Abstract

We present a time-dependent density-functional theory (TDDFT) with optimized effective potential (OEP) and self-interaction correction (SIC) for nonperturbative treatment of multiphoton and nonlinear optical processes of many-electron systems in intense laser fields. The resulting TDOEP/KLI-SIC equations are structurally similar to the time-dependent Hartree-Fock equations but include the many-body effects through an orbital-independent single-particle local time-dependent exchange-correlation (xc) potential. The method is applied to the all-electron study of the coherent control of multiple high-order harmonic generation (HHG) of He atoms in two-color mixed laser fields. A generalized pseudospectral time propagation method is introduced for efficient and accurate solution of the TDOEP/KLI-SIC equations in three spatial dimensions. It is found that the mixing of a strong second-harmonic (527 nm) field with a weak fundamental (1053 nm) field can lead to the production of both odd and even harmonics simultaneously with relatively high yield. Further, the relative efficiency of the HHG production can be controlled by varying the relative polarization of the two laser beams. The theoretical predictions are in accord with recent experimental observations. (C) 1998 John Wiley & Sons, Inc.