Thermodynamics of the disordered Hubbard model studied via numerical linked-cluster expansions

TL;DR

This paper investigates the thermodynamic properties of the disordered Fermi-Hubbard model using an extended numerical linked-cluster expansion technique, providing insights into disorder effects relevant for cold atom experiments.

Contribution

It extends the numerical linked-cluster expansion method to disordered quantum lattice models and applies it to study thermodynamics of the disordered Hubbard model.

Findings

Energy, double occupancy, entropy, heat capacity, and magnetic correlations vary with disorder strength.

Results agree with determinant quantum Monte Carlo simulations.

Findings are relevant for cold fermionic atom experiments.

Abstract

The interplay of disorder and strong correlations in quantum many-body systems remains an open question. That is despite much progress made in recent years with ultracold atoms in optical lattices to better understand phenomena such as many-body localization or the effect of disorder on Mott metal-insulator transitions. Here, we utilize the numerical linked-cluster expansion technique, extended to treat disordered quantum lattice models, and study exact thermodynamic properties of the disordered Fermi-Hubbard model on the square and cubic geometries. We consider box distributions for the disorder in the onsite energy, the interaction strength, as well as the hopping amplitude and explore how energy, double occupancy, entropy, heat capacity and magnetic correlations of the system in the thermodynamic limit evolve as the strength of disorder changes. We compare our findings with those obtained from determinant quantum Monte Carlo simulations and discuss the relevance of our results to experiments with cold fermionic atoms in optical lattices.