Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

1 Publication

Static Density Response of the Warm Dense Electron Gas beyond Linear Response Theory: Excitation of Harmonics

Böhme, M.; Dornheim, T.; Moldabekov, Z.; Vorberger, J.; Bonitz, M.

Experimental diagnostics as well as theoretical modeling of warm
dense matter (WDM) heavily rely on linear response theory.
However, Dornheim et. al. [Phys. Rev. Lett.125, 085001 (2020)]
showed that assuming the linear regime may not always be
justified in experiments studying WDM. In addition, the
intentional driving of non-linear effects should make new insight
into many-particle effects possible. We use ab initio Path-Integral
Monte-Carlo (PIMC) to obtain exact results for a harmonically
perturbed homogeneous electron gas. A thorough analysis for
different perturbation amplitudes is carried out. The
corresponding density response reveals resonances at the higher
harmonics of the perturbation wave vector. Analyzing the induced
density response as a function of the perturbation amplitude
shows the importance of the cubic response at the first harmonic
and of the quadratic response at the second harmonic.

Keywords: Warm Dense Matter; Path-Intergral Monte-Carlo

  • Poster (Online presentation)
    APS March Meeting, 15.-19.03.2021, Washington DC, USA

Publ.-Id: 32431