Interplay and competition between superconductivity and charge orderings in the zero-bandwidth limit of the extended Hubbard model with pair hopping and on-site attraction

Abstract

We present studies of an effective model which is a simple generalization of the standard model of a local pair superconductor with on-site pairing (i.e., the model of hard core bosons on a lattice) to the case of finite pair binding energy. The tight binding Hamiltonian consists of (i) the effective on-site interaction U, (ii) the intersite density-density interactions W between nearest-neighbours, and (iii) the intersite charge exchange term I, determining the hopping of electron pairs between nearest-neighbour sites. In the analysis of the phase diagrams and thermodynamic properties of this model we treat the intersite interactions within the mean-field approximation. Our investigations of the U<0 and W>0 case show that, depending on the values of interaction parameters, the system can exhibit three homogeneous phases: superconducting (SS), charge-ordered (CO) and nonordered (NO) as well as the phase separated SS-CO state.

4 pages, 3 figures; pdf-ReVTeX; Submitted to: JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM; presented also at PHASE SEPARATION AND SUPERSTRIPES in high temperature superconductors and related materials - SUPERSTRIPES (2012) - 55th Conference of INTERNATIONAL SCHOOL OF SOLID-STATE PHYSICS, Ettore Majorana Foundation, Centre for Scientific Culture, Erice - Italy: July 11-17, 2012

References in corpus (6)

• One-dimensional extended Hubbard model in the atomic limit
• Phase separation in a lattice model of a superconductor with pair hopping
• The magnetic field induced phase separation in a model of a superconductor with local electron pairing
• Some properties of the model of a superconductor with pair hopping and magnetic interactions at half-filling
• Stable and metastable phases in the atomic limit of the extended Hubbard model with intersite density-density interactions
• Interplay between charge and magnetic orderings in the zero-bandwidth limit of the extended Hubbard model for strong on-site repulsion

Cited by in corpus (6)

• Metastability and phase separation in a simple model of a superconductor with extremely short coherence length
• Some properties of two dimensional extended repulsive Hubbard model with intersite magnetic interactions - a Monte Carlo study
• Superconductivity, metastability and magnetic field induced phase separation in the atomic limit of the Penson-Kolb-Hubbard model
• Probe-type of superconductivity by impurity in materials with short coherence length: the s-wave and $\eta$-wave phases study
• Pseudotransitions in a dilute Ising chain
• Some exact results for the zero-bandwidth extended Hubbard model with intersite charge and magnetic interactions