High energy kink in the single particle spectra of the two-dimensional Hubbard model

TL;DR

This study uses quantum Monte Carlo simulations to reveal a high energy kink in the spectral weight of the 2D Hubbard model, attributed to scattering with high energy spin fluctuations, aligning with experimental ARPES findings in cuprates.

Contribution

The paper demonstrates that the high energy kink in the Hubbard model spectra arises from coupling to damped high energy spin fluctuations, providing a theoretical explanation consistent with experiments.

Findings

Identification of a high energy kink in the spectral weight.

Agreement between Monte Carlo results and a spin fluctuation coupling model.

Attribution of the kink to scattering with high energy spin fluctuations.

Abstract

Employing dynamical cluster quantum Monte Carlo calculations we show that the single particle spectral weight A(k,w) of the one-band two-dimensional Hubbard model displays a high energy kink in the quasiparticle dispersion followed by a steep dispersion of a broad peak similar to recent ARPES results reported for the cuprates. Based on the agreement between the Monte Carlo results and a simple calculation which couples the quasiparticle to spin fluctuations, we conclude that the kink and the broad spectral feature in the Hubbard model spectra is due to scattering with damped high energy spin fluctuations.