Temperature and filling dependence of the superconducting $\pi$-phase in the Penson-Kolb-Hubbard model

Abstract

We investigate in the Hartree Fock approximation the temperature and filling dependence of the superconducting $\pi$-phase for the Penson-Kolb-Hubbard model. Due to the presence of the pair-hopping term, the phase survives for repulsive values of the on-site Coulomb interaction, exhibiting an interesting filling and temperature dependence. The structure of the self-consistent equations peculiar to the $\pi$-phase of the model allows to explicitly solve them for the chemical potential. The phase diagrams are shown and discussed in dimension 2 and 3. We also show that, when a next-nearest neighbours hopping term is included, the critical temperature of the superconducting region increases, and the corresponding range of filling values is shifted away from half-filling. Comparison with known exact results is also discussed.

20 pages, REVTEX, 8 eps figures

References in corpus (3)

• Superconductivity in the Hubbard model with pair hopping
• Improved stability regions for ground states of the extended Hubbard model
• Maximal Stability Regions for Superconducting Ground States of Generalized Hubbard Models

Cited by in corpus (8)

• Phase separation in a lattice model of a superconductor with pair hopping
• Critical field in a model with local pairs
• Quantum phases of 1D Hubbard models with three- and four-body couplings
• The magnetic field induced phase separation in a model of a superconductor with local electron pairing
• Phase separation of superconducting phases in the Penson-Kolb-Hubbard model
• Exact thermodynamics of an Extended Hubbard Model of single and paired carriers in competition
• Thermodynamic and electromagnetic properties of the eta-pairing superconductivity in the Penson-Kolb model
• Mixing of $d_{x^2-y^2}$ and $d_{xy}$ superconducting states for different filling and temperature