Effects of nanoscale spatial inhomogeneity in strongly correlated systems

TL;DR

This paper investigates how nanoscale spatial inhomogeneity affects the ground-state energies and density distributions in strongly correlated Hubbard superlattices, revealing that small potential variations can significantly influence system behavior.

Contribution

It demonstrates the impact of nanoscale inhomogeneity on strongly correlated systems and compares computational methods for analyzing these effects.

Findings

Small potential variations can counteract effects of larger interaction variations

Nanoscale inhomogeneity significantly influences system properties

Reevaluation of models assuming spatial homogeneity is necessary

Abstract

We calculate ground-state energies and density distributions of Hubbard superlattices characterized by periodic modulations of the on-site interaction and the on-site potential. Both density-matrix renormalization group and density-functional methods are employed and compared. We find that small variations in the on-site potential $v_i$ can simulate, cancel, or even overcompensate effects due to much larger variations in the on-site interaction $U_i$. Our findings highlight the importance of nanoscale spatial inhomogeneity in strongly correlated systems, and call for reexamination of model calculations assuming spatial homogeneity.