Nonlinear interaction of external perturbations in warm dense matter. Issue 10 (8th February 2022)

• Record Type: Journal Article
• Authors: Dornheim, Tobias; Vorberger, Jan; Moldabekov, Zhandos A.; Bonitz, Michael
• Other Names: Kraus Dominik guestEditor.; Vorberger Jan guestEditor.; Redmer Ronald guestEditor.; Glenzer Siegfried H. guestEditor.
• Is Part Of: Contributions to plasma physics. Volume 62:Issue 10(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-02-08
• Subjects: nonlinear density response -- path integral Monte Carlo -- warm dense matter; Plasma (Ionized gases) -- Periodicals; Electronic journals; 530.44
• DOI: 10.1002/ctpp.202100247
• Languages: English
• ISSNs: 0863-1042

Abstract

Abstract: We present extensive new ab initio path integral Monte Carlo (PIMC) results for an electron gas at warm dense matter conditions that is subject to multiple harmonic perturbations. In addition to the previously investigated nonlinear effects at the original wave number (Dornheim et al., Phys. Rev. Lett., 2020, 125, 085001) and the excitation of higher harmonics (Dornheim et al., Phys. Rev. Res., 2021, 3, 033231), the presence of multiple external potentials leads to mode‐coupling effects, which constitute the dominant nonlinear effect and lead to a substantially more complicated density response compared to linear response theory. One possibility to estimate mode‐coupling effects from a PIMC simulation of the unperturbed system is given in terms of generalized imaginary‐time correlation functions that have been recently introduced by Dornheim et al. (J. Chem. Phys., 2021, 155, 054110). In addition, we extend our previous analytical theory of the nonlinear density response of the electron gas in terms of the static local field correction (Dornheim et al., 2020, Phys. Rev. Lett., 125, 235001), which allows for a highly accurate description of the PIMC results with negligible computational cost.