Effect of the hole doping into the Haldane-gap state on the one-dimensional S = 1 t−J model

Abstract

arXiv:cond-mat/9511035v1 7 Nov 1995 Effect of the hole doping into the Haldane-gap state on the one-dimensional S = 1 t-J model Yoshihiro Nishiyama and Masuo Suzuki Department of Physics, University of Tokyo Hongo 7-3-1, Bunkyo-ku, Tokyo 113, Japan (Received ) AbstractThe ground state and excitation spectra of the S = 1 Heisenberg spin chain with hole hopping are investigated by means of the numerical-diagonalization method and by the help of the Zhang-Arovas picture. As for the charge sector, two phases are found. It is shown that in the weak-hopping region, a phase separation occurs, while in the strong-hopping region, the system is in the Tomonaga-Luttinger liquid phase. Irrespective of the presence of the spin gap, the present phase diagram is similar to that reported for the S = 1/2 t-J chain with gapless spin excitation rather than to that for the magnetically-frustrated t-J chain with spin gap. For the spin sector, the string correlation is found to develop withstanding the hole doping except in a region, whose region is characterized by a generalized string correlation.This remains an open question to be studied in future.

Competing orders and hidden duality symmetries in two-leg spin ladder systems

“…(116)). In fact, numerical simulations carried out for the spin-1 bosonic t-J model 81 (the set of parameters B = D = t/2, A = J, C = 0 was used there) show the existence of a finite spin gap and the Luttinger-liquid behavior in the pseudo-charge sector, which is consistent with our conclusion in section V A. Now that we know that the spin sector is generically gapped and decoupled from the pseudo-charge sector, the next question would be what kind of degrees of freedom determines the global structure of the phase diagram.…”