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Effects of nanoscale spatial inhomogeneity in strongly correlated systems

M. F. Silva·N. A. Lima·A. L. Malvezzi·K. Capelle
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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.

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M. F. Silva, N. A. Lima, A. L. Malvezzi, K. Capelle. 2005-02-15. Effects of nanoscale spatial inhomogeneity in strongly correlated systems. https://doi.org/10.1103/physrevb.71.125130

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