Effect of singlet pairing hopping on the one-dimensional extended Hubbard model with spin exchange interaction
School of Physical Science and Technology, Xinjiang University,
Received: 11 April 2012
Received in final form: 4 May 2012
Published online: 18 June 2012
The ground-state properties of the one-dimensional (1D) t-U-J model with singlet pair hopping interaction are studied in the weak-coupling regime. The analysis of the model with U(1) ⊗ SU(2) symmetry is performed using the bosonization and renormalization-group approaches. At half filling the phase diagram is shown to consist of three different insulating states corresponding to the Peierls dimerized bond-charge-density-wave (BCDW) phase, the spin-density-wave (SDW) phase and the bond-spin-density-wave (BSDW) phase, and two different superconducting states with the singlet-superconducting (SS) phase and the triplet-superconducting (TS) phase. Moreover, the SDW, BSDW and TS phases are all degenerated. The result indicates that the pair hopping interaction P has a strong effect on the ground-state properties of 1D correlated electron systems.
Key words: Solid State and Materials
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2012