# Magnetic Susceptibility and Simulated Neutron Signal in the 2D Hubbard Model

## TL;DR

This paper computes and compares dynamic spin susceptibilities in the 2D Hubbard model using advanced methods, relating findings to neutron experiments on cuprates, and explores how spin excitations evolve with interaction strength and doping.

## Contribution

It introduces a comprehensive analysis of spin susceptibilities in the 2D Hubbard model using Dual Fermions, comparing results with other methods and experimental data, highlighting the evolution of spin excitations.

## Key findings

- Identification of spin modes via peaks in Imχ(ω,q)
- Observation of a 'Y'-shaped dispersion similar to experiments
- Analysis of the evolution of spin excitations with doping and interaction strength

## Abstract

We compute dynamic spin susceptibilities in the two-dimensional Hubbard model using the method of Dual Fermions and provide comparison to lattice Monte Carlo and cluster dynamical mean field theory. We examine the energy dispersion identified by peaks in ${\rm Im}\chi(\omega,q)$ which define spin modes and compare the exchange scale and magnon dispersion to neutron experiments on the parent La$_2$CuO$_4$ cuprate. We present the evolution of the spin excitations as a function of Hubbard interaction strengths and doping and explore the particle-hole asymmetry of the spin excitations. We also study the correlation lengths and the spin excitation dispersion peak structure and find a `Y'-shaped dispersion similar to neutron results on doped HgBa$_2$CuO$_{4+\delta}$.