We define a chain-cluster Fermi-linearized Hubbard model, in which the hopping between adjacent 1-d chains is described in terms of an order parameter (valued in a suitable Grassmann field) describing the (transverse) intra-bond correlation, whereas the intra-chain hopping is treated rigorously. The free energy of the 2-d Hubbard model, where neighbouring chains are connected by hopping processes, can be straightforwardly reconducted to that—evaluated self-consistently—of the 1-d model. The self-consistency equations for the one-dimensional chain, when solved explicitly using the exact Lieb-Wu-Takahashi equations, lead to the appearance of a phase transition, for finite values of the Coulomb repulsion strength U (U>U c, where U c is a critical finite value of U), which can be interpreted as evidence for a mott-Hubbard-type metal-insulator transition.

MOTT-HUBBARD METAL-INSULATOR-TRANSITION - A CHAIN-CLUSTER FERMI-LINEARIZED APPROACH TO THE 2-D HUBBARD SYSTEM / Montorsi, Arianna; Rasetti, Mario. - In: NUOVO CIMENTO DELLA SOCIETÀ ITALIANA DI FISICA. D CONDENSED MATTER, ATOMIC, MOLECULAR AND CHEMICAL PHYSICS, BIOPHYSICS. - ISSN 0392-6737. - 16:(1994), pp. 1649-1657. [10.1007/BF02462155]

MOTT-HUBBARD METAL-INSULATOR-TRANSITION - A CHAIN-CLUSTER FERMI-LINEARIZED APPROACH TO THE 2-D HUBBARD SYSTEM

MONTORSI, Arianna;RASETTI, Mario
1994

Abstract

We define a chain-cluster Fermi-linearized Hubbard model, in which the hopping between adjacent 1-d chains is described in terms of an order parameter (valued in a suitable Grassmann field) describing the (transverse) intra-bond correlation, whereas the intra-chain hopping is treated rigorously. The free energy of the 2-d Hubbard model, where neighbouring chains are connected by hopping processes, can be straightforwardly reconducted to that—evaluated self-consistently—of the 1-d model. The self-consistency equations for the one-dimensional chain, when solved explicitly using the exact Lieb-Wu-Takahashi equations, lead to the appearance of a phase transition, for finite values of the Coulomb repulsion strength U (U>U c, where U c is a critical finite value of U), which can be interpreted as evidence for a mott-Hubbard-type metal-insulator transition.
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11583/1674197
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