Variational state based on the Bethe-ansatz solution and a correlated singlet liquid state in the one-dimensional t-J model
Abstract
The one-dimensional t-J model is investigated by the variational Monte Carlo method. A variational wave function based on the Bethe-ansatz solution is proposed, where the spin-charge separation is realized and a long-range correlation factor of Jastrow-type is included. In most regions of the phase diagram, this wave function provides an excellent description of the ground-state properties characterized as a Tomonaga-Luttinger liquid; both the amplitude and exponent of correlation functions are correctly reproduced. For the spin-gap phase, another trial state of correlated singlet pairs with a Jastrow factor is introduced. This wave function shows generalized Luther-Emery-liquid behavior, exhibiting enhanced superconducting correlations and exponential decay of the spin correlation function. Using these two variational wave functions, the whole phase diagram is determined. In addition, relations between the correlation exponent and variational parameters in the trial functions are derived.
- Publication:
-
Physical Review B
- Pub Date:
- November 1996
- DOI:
- 10.1103/PhysRevB.54.13129
- arXiv:
- arXiv:cond-mat/9608114
- Bibcode:
- 1996PhRvB..5413129K
- Keywords:
-
- 74.20.Mn;
- 71.10.Hf;
- 71.10.Pm;
- 71.27.+a;
- Nonconventional mechanisms;
- Non-Fermi-liquid ground states electron phase diagrams and phase transitions in model systems;
- Fermions in reduced dimensions;
- Strongly correlated electron systems;
- heavy fermions;
- Condensed Matter
- E-Print:
- REVTeX 3.0, 27 pages. 7 figures available upon request (koba@cc.it-chiba.ac.jp). To be published in Phys. Rev. B 54