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arXiv · 0903.1544

The two-orbital Hubbard model and the OSMT

Adolfo Avella·Ferdinando Mancini·Satoru Odashima·Giovanni Scelza
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Abstract

We analyze the two-orbital Hubbard model by means of the Composite Operator Method with the aim at studying the phenomenon of orbital selective Mott transition (OSMT). The model contains an interorbital interaction $U'$, in addition to the usual intraorbital one $U$. As warming-up approximation, we use a basis of two operators only, the Hubbard operators. The analysis of the density of states at the chemical potential as a function of the ratio between the bandwidths of the two orbitals shows the clear signature of an orbital selective Mott transition as expected.

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Adolfo Avella, Ferdinando Mancini, Satoru Odashima, Giovanni Scelza. 2009-06-17. The two-orbital Hubbard model and the OSMT. https://doi.org/10.1016/j.physc.2007.03.218

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