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arXiv · 1702.04952

Nonequilibrium GW+EDMFT: Antiscreening and inverted populations from nonlocal correlations

Denis Golez·Lewin Boehnke·Hugo Strand·Martin Eckstein·Philipp Werner
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Abstract

We study the dynamics of screening in photo-doped Mott insulators with long-ranged interactions using a nonequilibrium implementation of the $GW$ plus extended dynamical mean field theory ($GW$+EDMFT) formalism. Our study demonstrates that the complex interplay of the injected carriers with bosonic degrees of freedom (charge fluctuations) can result in long-lived transient states with properties that are distinctly different from those of thermal equilibrium states. Systems with strong nonlocal interactions are found to exhibit a self-sustained population inversion of the doublons and holes. This population inversion leads to low-energy antiscreening which can be detected in time-resolved electron-energy loss spectra.

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Denis Golez, Lewin Boehnke, Hugo Strand, Martin Eckstein, Philipp Werner. 2017-02-16. Nonequilibrium GW+EDMFT: Antiscreening and inverted populations from nonlocal correlations. https://doi.org/10.1103/physrevlett.118.246402

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