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Band and filling controlled transitions in exactly solved electronic models

F. Dolcini·A. Montorsi
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Abstract

We describe a general method to study the ground state phase diagram of electronic models on chains whose extended Hubbard hamiltonian is formed by a generalized permutator plus a band-controlling term. The method, based on the appropriate interpretation of Sutherland's species, yields under described conditions a reduction of the effective Hilbert space. In particular, we derive the phase diagrams of two new models; the first one exhibits a band-controlled insulator-superconductor transition at half-filling for the unusually high value $U_c=6 t$; the second one is characterized by a filling-controlled metal-insulator transition between two finite regions of the diagram.

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F. Dolcini, A. Montorsi. 2000-09-20. Band and filling controlled transitions in exactly solved electronic models. https://doi.org/10.1103/physrevb.63.121103

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