Ferromagnetically ordered metal in the single-band Hubbard model

TL;DR

This paper investigates ferromagnetic instability in the single-band Hubbard model using dynamical mean-field theory and quantum Monte Carlo simulations, revealing how magnetic fluctuations depend on interaction strength and doping.

Contribution

It provides a systematic analysis of ferromagnetic fluctuations across different coupling regimes and discusses the efficiency of simulation algorithms.

Findings

Ferromagnetic fluctuations are enhanced with increased interaction strength.

Magnetic susceptibility varies systematically with hole density.

The study demonstrates the effectiveness of the segment algorithm in simulations.

Abstract

We study a ferromagnetic instability in a single-band Hubbard model on the hypercubic lattice away from half filling. Using dynamical mean-field theory with the continuous-time quantum Monte Carlo simulations based on the segment algorithm, we calculate the magnetic susceptibility in the weak and strong coupling regions systematically. We then find how ferromagnetic fluctuations are enhanced when the interaction strength and density of holes are varied. The efficiency of the double flip updates in the Monte Carlo simulations is also addressed.