Probing the pseudogap and beyond: examining single-particle properties of the hole- and electron-doped Hubbard model

TL;DR

This study uses advanced quantum Monte Carlo simulations to explore the electronic properties of the Hubbard model, revealing asymmetries between electron and hole doping and insights into the pseudogap phenomenon relevant to cuprate superconductors.

Contribution

It provides high-resolution spectral data showing doping asymmetries and the nature of the pseudogap, advancing understanding of strongly correlated electron systems.

Findings

Electron doping shows more coherent quasiparticles and stronger antiferromagnetic correlations.

A nodal-antinodal dichotomy appears at low doping, similar to cuprates.

The pseudogap emerges as a smooth crossover without pocket formation.

Abstract

We compute high-resolution angle-resolved photoemission spectroscopy of the Hubbard model using the unbiased determinant quantum Monte Carlo algorithm, revealing an asymmetry between electron and hole doping. Electron doping exhibits more coherent quasiparticles and stronger antiferromagnetic correlations compared to hole doping. At low doping, a nodal-antinodal dichotomy on the Fermi surface is observed, similar to cuprate experiments. The dichotomy reflects the momentum dependence of the Mott gap, as manifested in both the spectral function and the self-energy. For hole doping, we observe a transition towards the pseudogap, without signature of pocket formation. The simulated nuclear magnetic resonance pseudogap temperatures do not necessarily agree with the temperature determined by spectroscopy. These findings collectively suggest the pseudogap is a smooth crossover driven by strong correlations.