Electrical conductivity of high-pressure liquid hydrogen by quantum Monte Carlo methods

TL;DR

This study uses quantum Monte Carlo methods to calculate the electrical conductivity of high-pressure liquid hydrogen, revealing a transition from semiconductor to metal and aligning well with experimental shock-wave data.

Contribution

It introduces a novel quantum Monte Carlo approach combining coupled electron-ion sampling with many-body eigenstate calculations for conductivity.

Findings

Identifies a liquid semiconductor to metal transition at high pressure.

Provides conductivity values consistent with shock-wave experiments.

Demonstrates the effectiveness of quantum Monte Carlo in high-pressure liquid hydrogen.

Abstract

We compute the electrical conductivity for liquid hydrogen at high pressure using quantum Monte Carlo. The method uses Coupled Electron-Ion Monte Carlo to generate configurations of liquid hydrogen. For each configuration correlated sampling of electrons is performed in order to calculate a set of lowest many-body eigenstates and current-current correlation functions of the system, which are summed over in the many-body Kubo formula to give AC electrical conductivity directly. The extrapolated DC conductivity at 3000 K for several densities shows a liquid semiconductor to liquid-metal transition at high pressure. Our results are in good agreement with shock-wave data.