Multielectron effects in high harmonic generation in N2 and benzene: simulation using a non-adiabatic quantum molecular dynamics approach for laser-molecule interactions

Abstract

A mixed quantum-classical approach is introduced which allows the dynamical response of molecules driven far from equilibrium to be modeled. This method is applied to the interaction of molecules with intense, short-duration laser pulses. The electronic response of the molecule is described using time-dependent density functional theory (TDDFT) and the resulting Kohn-Sham equations are solved numerically using finite difference techniques in conjunction with local and global adaptations of an underlying grid in curvilinear coordinates. Using this approach, simulations can be carried out for a wide range of molecules and both all-electron and pseudopotential calculations are possible. The approach is applied to the study of high harmonic generation in N2 and benzene using linearly-polarized laser pulses and, to the best of our knowledge, the results for benzene represent the first TDDFT calculations of high harmonic generation in benzene using linearly polarized laser pulses. For N2 an enhancement of the cut-off harmonics is observed whenever the laser polarization is aligned perpendicular to the molecular axis. This enhancement is attributed to the symmetry properties of the Kohn-Sham orbital that responds predominantly to the pulse. In benzene we predict that a suppression in the cut-off harmonics occurs whenever the laser polarization is aligned parallel to the molecular plane. We attribute this suppression to the symmetry-induced response of the highest-occupied molecular orbital.

References in corpus (7)

• Parallel Self-Consistent-Field Calculations via Chebyshev-Filtered Subspace Acceleration
• A time-dependent approach to electron pumping in open quantum systems
• Intensity dependence of multiple orbital contributions and shape resonance in high-order harmonic generation of aligned N${}_2$ molecules}
• Uncovering multiple orbitals influence in high harmonic generation from aligned N${}_2$
• Robust ultrafast currents in molecular wires through Stark shifts
• All-electron density functional theory and time-dependent density functional theory with high-order finite elements
• Coherent laser control of the current through molecular junctions

Cited by in corpus (8)

• High-order-harmonic generation in benzene with linearly and circularly polarised laser pulses
• High-order harmonic generation from highly-excited states in acetylene
• Unexpected dipole instabilities in small molecules after ultrafast XUV irradiation
• Multielectron effects in strong-field ionization of benzene derivatives
• R-Matrix incorporating Time (RMT) method for H2+ in short and intense laser fields
• Influence of coherent vibronic excitation on the high harmonics generation of diatomic molecules
• Probing the role of excited states in ionization of acetylene
• Implementation of a time-dependent multiconfiguration self-consistent-field method for coupled electron-nuclear dynamics in diatomic molecules driven by intense laser pulses