The two-orbital Hubbard model and the OSMT

Adolfo Avella; Ferdinando Mancini; Satoru Odashima; Giovanni Scelza

doi:10.1016/j.physc.2007.03.218

paper

The two-orbital Hubbard model and the OSMT

arXiv:0903.1544 · doi:10.1016/j.physc.2007.03.218

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.

2 pages, 1 figure