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arXiv · 1301.1916

Bohmian trajectory analysis of high-order harmonic generation: ensemble averages, non-locality and quantitative aspects

J. Wu·B. B. Augstein·C. Figueira de Morisson Faria
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Abstract

We perform a Bohmian-trajectory analysis of high-order harmonic generation (HHG), focusing on the fact that typical HHG spectra are best reproduced by the Bohmian trajectory starting at the innermost part of the core [Phys. Rev. A \textbf{88}, 023415 (2013)]. Using ensemble averages around this central trajectory, we show that, for the high-plateau and cutoff harmonics, small ensembles of Bohmian trajectories are sufficient for a quantitative agreement with the numerical solution of the time-dependent Schrödinger equation (TDSE), while larger ensembles are necessary in the low-plateau region. Furthermore, we relate the Bohmian trajectories to the "short" and "long" trajectories encountered in the Strong-Field Approximation (SFA), and show that the time-frequency maps from the central Bohmian trajectory overestimate the contributions of the long SFA trajectory, in comparison to the outcome of the TDSE computations. We also discuss how the time-frequency profile of the central trajectory may be influenced nonlocally by degrading the wave-packet propagation far from the core.

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J. Wu, B. B. Augstein, C. Figueira de Morisson Faria. 2013-12-19. Bohmian trajectory analysis of high-order harmonic generation: ensemble averages, non-locality and quantitative aspects. https://doi.org/10.1103/physreva.88.063416

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