Mixed Phase and Bound States in the Phase Diagram of the Extended Hubbard Model

• Authors: M. Bąk
• Languages of publication: EN

Abstracts

EN

The paper examines part of the ground state diagram of the extended Hubbard model, with the on-site attraction U<0 and intersite repulsion W>0 in the presence of charge density waves, superconducting andη-superconducting order parameters. We show the possibility of the stabilization of the mixed state, with all three nonzero order parameters, in the model with nearest neighbor interactions. The other result of the paper is application of the exact solution of the Schrödinger equation for the two-electron bound state, as an additional bound for the phase diagram of the model, resulting in the partial suppression of the superconducting state of the s-wave symmetry, in favor of the normal state phase.

Keywords

EN

71.10.Fd; 71.10.Hf; 71.27.+a

Discipline

• 71.27.+a: Strongly correlated electron systems; heavy fermions
• 71.10.Fd: Lattice fermion models (Hubbard model, etc.)
• 71.10.Hf: Non-Fermi-liquid ground states, electron phase diagrams and phase transitions in model systems

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2004
• Volume: 106
• Issue: 5
• Pages: 637-646

Dates

published

2004-11

received

2004-06-06

Contributors

author

M. Bąk

• Institute of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland

References

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Identifiers

DOI

10.12693/APhysPolA.106.637