arXiv:1510.04749 · Journal of Physics Conference Series

Intersite electron correlations in a Hubbard model on inhomogeneous lattices

Nayuta Takemori, Akihisa Koga, Hartmut Hafermann

Published Feb 5, 2016• 5 citations

Abstract

We study intersite electron correlations in the half-filled Hubbard model on square lattices with periodic and open boundary conditions by means of a real-space dual fermion approach. By calculating renormalization factors, we clarify that nearest-neighbor intersite correlations already significantly reduce the critical interaction. The Mott transition occurs at U/t ∼ 6.4, where U is the interaction strength and t is the hopping integral. This value is consistent with quantum Monte Carlo results. It shows the importance of short-range intersite correlations, which are taken into account in the framework of the real-space dual fermion approach.

DOI: 10.1088/1742-6596/683/1/012040

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