Strongly Correlated Electrons in Atomic Liquids: Gutzwiller Molecular Dynamics Simulations 255 views

In this thesis, we study the intricate interplay between the electronic structure and atomic distribution in liquid metal models featuring electron-electron interaction. In Chapter 2, we introduce the model employed to examine correlated electrons in liquids. Furthermore, we delve into the Gutzwiller variational method, offering an in-depth discussion alongside modern formulations. Additionally, we detail the implementation of Gutzwiller molecular dynamics for our study. In chapter 3, we study the influence of the atomic distribution on the electronic structure. Our focus lies in the Mott transition in metallic liquids, and draws comparisons to its manifestation in amorphous solids. We demonstrate a rather counter-intuitive phenomenon in metallic fluids where the electrical conductivity of a liquid system can be enhanced by electron correlation effects. We show that while electron hopping is indeed suppressed by a larger Hubbard repulsion, the reduced electronic cohesive forces give rise to atomic clusters with a larger coordination number. The increased atomic connectivity in turn results in an enhanced electrical conductance. In Chapter 4, we delve into the impact of electron localization on atomic transport properties. Our investigation unveils an unusual peak in atomic diffusion in proximity to the Mott transition in the Hubbard liquid model. To elucidate this intriguing observation, we proposed a general theory based on the Chapman-Enskog method. Remarkably, our theoretical framework successfully replicates this phenomenon in classical simple liquids. In chapter 5, we employed the Gutzwiller molecular dynamics to study the liquid-liquid transition in dense hydrogen. We constructed an ab initio tight-binding model tailored specifically for hydrogen. Our simulation results characterise a metal-insulator transition in liquid hydrogen. Notably, this transition arises not from correlated interactions but rather from the dissociation of hydrogen molecules.

PHD (Doctor of Philosophy)

English

2024-04-30