Pseudogaps and their Interplay with Magnetic Excitations in the doped 2D Hubbard Model

TL;DR

This study uses Quantum Monte Carlo simulations to explore how pseudogaps and magnetic excitations evolve with doping in the 2D Hubbard model, revealing their interconnected nature and underlying antiferromagnetic origins.

Contribution

It provides a detailed analysis linking pseudogap behavior with magnetic excitations across doping levels in the 2D Hubbard model, supported by simulation data.

Findings

Pseudogap features match experimental photoemission data.

Magnetic response sharpens in underdoped regime, broadens with doping.

Antiferromagnetic remnants influence pseudogap evolution.

Abstract

On the basis of Quantum Monte Carlo simulations of the two-dimensional Hubbard model which cover the doping range from the under- to the over-doped regime, we find that the single-particle spectral weight $A (\vec k,\omega)$ qualitatively reproduces both the momentum ($d_{x^2-y^2}$--symmetry) and doping dependence of the pseudogap as found in photoemission experiments. The drastic doping dependence of the spin response $\chi_{s} (\vec q,\omega)$ which is sharp in both $\vec q (\approx(\pi,\pi))$ and $\omega$ in the under-doped regime but broad and structureless otherwise, identifies remnants of the antiferromagnetic order as the driving mechanism behind the pseudogap and its evolution with doping.