Theory of Attosecond Transient Absorption Spectroscopy of Krypton for Overlapping Pump and Probe Pulses
arXiv:1212.1589 · doi:10.1103/PhysRevA.86.063411
Abstract
We present the first fully ab initio calculations for attosecond transient absorption spectroscopy of atomic krypton with overlapping pump and probe pulses. Within the time-dependent configuration interaction singles (TDCIS) approach, we describe the pump step (strong-field ionization using a near-infrared pulse) as well as the probe step (resonant electron excitation using an extreme- ultraviolet pulse) from first principles. We extent our TDCIS model and account for the spin-orbit splitting of the occupied orbitals. We discuss the spectral features seen in a recent attosecond transient absorption experiment [A. Wirth et al., Science 334, 195 (2011)]. Our results support the concept that the transient absorption signal can be directly related to the instantaneous hole population even during the ionizing pump pulse. Furthermore, we find strong deformations in the absorption lines when the overlap of pump and probe pulses is maximum. These deformations can be described by relative phase shifts in the oscillating ionic dipole. We discuss possible mechanisms contributing to these phase shifts. Our finding suggests that the non-perturbative laser dressing of the entire N -electron wave function is the main contributor.
15 page, 10 figures, Phys. Rev. A (accepted)
References in corpus (5)
- Decoherence in Attosecond Photoionization
- Femtosecond induced transparency and absorption in the extreme ultraviolet by coherent coupling of the He 2s2p (1P0) and 2p2 (1Se) double excitation states with 800 nm light
- The Impact of Multichannel and Multipole Effects on the Cooper Minimum in the High-Harmonics Spectrum of Argon
- Theory of high-order harmonic generation from molecules by intense laser pulses
- Photoabsorption of attosecond XUV light pulses by two strongly laser-coupled autoionizing states