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arXiv · 1111.1119

Phase transitions and spectral properties of the ionic Hubbard model in one dimension

Ara Go·Gun Sang Jeon
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Abstract

The ionic Hubbard model is investigated at half filling at zero temperature. We apply the cellular dynamical mean-field theory to the one-dimensional ionic Hubbard model to compute local quantities such as double occupancy and staggered charge density. Both quantities provide general transition behavior of the model from a band insulating phase to a Mott insulating phase. The renormalized band gap is introduced as an efficient order parameter for the transition from a band insulator. We also present the spectral properties of the ionic Hubbard model, which exhibit characteristic features for both weak and strong interactions.

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Ara Go, Gun Sang Jeon. 2011-11-04. Phase transitions and spectral properties of the ionic Hubbard model in one dimension. https://doi.org/10.1103/physrevb.84.195102

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