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arXiv · 1605.00703

Time-dependent complete-active-space self-consistent-field method for atoms: Application to high-harmonic generation

Takeshi Sato·Kenichi L. Ishikawa·Iva Brezinova·Fabian Lackner·Stefan Nagele·Joachim Burgdorfer
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Abstract

We present the numerical implementation of the time-dependent complete-active-space self-consistent-field (TD-CASSCF) method [Phys. Rev. A, 88, 023402 (2013)] for atoms driven by a strong linearly polarized laser pulse. The present implementation treats the problem in its full dimensionality and introduces a gauge-invariant frozen-core approximation, an efficient evaluation of the Coulomb mean field scaling linearly with the number of basis functions, and a split-operator method specifically designed for stable propagation of stiff spatial derivative operators. We apply this method to high-harmonic generation in helium, beryllium, and neon and explore the role of electron correlations.

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Takeshi Sato, Kenichi L. Ishikawa, Iva Brezinova, Fabian Lackner, Stefan Nagele, Joachim Burgdorfer. 2016-05-02. Time-dependent complete-active-space self-consistent-field method for atoms: Application to high-harmonic generation. https://doi.org/10.1103/physreva.94.023405

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