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arXiv · 0902.1076

Insulating behavior with spin and charge order in the ionic Hubbard model

Krzysztof Byczuk·Michael Sekania·Walter Hofstetter·Arno P. Kampf
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Abstract

Paramagnetic solutions of the ionic Hubbard model at half-filling in dimensions $D>2$ indicate that the band and the Mott insulator phases are separated by a metallic phase. We present zero-temperature dynamical mean-field theory solutions, which include antiferromagnetic long-range order, and show that the one-particle spectral functions always possess an energy gap and therefore the system is insulating for all interaction strengths. The staggered charge density modulation coexists with antiferromagnetic long-range order of Néel type.

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Krzysztof Byczuk, Michael Sekania, Walter Hofstetter, Arno P. Kampf. 2009-02-06. Insulating behavior with spin and charge order in the ionic Hubbard model. https://doi.org/10.1103/physrevb.79.121103

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