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arXiv · 1611.00888

Accurate high-harmonic spectra from time-dependent two-particle reduced density matrix theory

Fabian Lackner·Iva Březinová·Takeshi Sato·Kenichi L. Ishikawa·Joachim Burgdörfer
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Abstract

The accurate description of the non-linear response of many-electron systems to strong-laser fields remains a major challenge. Methods that bypass the unfavorable exponential scaling with particle number are required to address larger systems. In this paper we present a fully three-dimensional implementation of the time-dependent two-particle reduced density matrix (TD-2RDM) method for many-electron atoms. We benchmark this approach by a comparison with multi-configurational time-dependent Hartree-Fock (MCTDHF) results for the harmonic spectra of beryllium and neon. We show that the TD-2RDM is very well-suited to describe the non-linear atomic response and to reveal the influence of electron-correlation effects.

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Fabian Lackner, Iva Březinová, Takeshi Sato, Kenichi L. Ishikawa, Joachim Burgdörfer. 2016-11-03. Accurate high-harmonic spectra from time-dependent two-particle reduced density matrix theory. https://doi.org/10.1103/physreva.95.033414

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