Dynamic Response of an Electron Gas: Towards the Exact Exchange-Correlation Kernel.

Area of Science:

• Condensed matter physics
• Computational materials science

Background:

• Accurate modeling of electron gas dynamics is essential for new materials development.
• The jellium model provides a fundamental framework for these calculations.

Purpose of the Study:

• To introduce a novel diagrammatic Monte Carlo technique for calculating frequency and momentum-resolved finite temperature response.
• To extract the frequency dependence of the exchange-correlation kernel at finite temperatures and momenta.

Main Methods:

• Diagrammatic Monte Carlo technique utilizing algorithmic Matsubara integration.
• Direct computation in the real frequency domain via Feynman diagrams.
• Analysis of charge response data at moderate electron densities.

Main Results:

• Successful computation of frequency and momentum-resolved finite temperature response.
• Extraction of the frequency-dependent exchange-correlation kernel.
• Demonstration of the method's applicability to materials relevant densities.

Conclusions:

• The developed method offers a direct route to finite temperature, real-frequency dynamics.
• This approach is vital for improving time-dependent density functional theory for materials.
• The findings are as significant for dynamics as ground state energies are for static properties.