Phase Diagram of S=1 BondAlternating XXZ Chains Reflecting the Hidden Z_2\times Z_2 Symmetry
Abstract
The phase diagram of the spin1 bondalternating XXZ chain is studied numerically. This model is appropriate to study the VBS picture and the hidden Z_2\times Z_2 symmetry concerning to the Haldane gap problem. The possible phases are the ferromagnetic, the XY, the Haldane, the dimer, and the Néel ones. The critical properties of this model can be interpreted as the AshkinTeller type reflecting the hidden Z_2\times Z_2 symmetry. The phase transitions are of the BerezinskiiKosterlitzThouless type (XYHaldane and XYdimer), of the 2D Gaussian type (Haldanedimer), and of the 2D Ising type (HaldaneNéel and dimerNéel). We determine the phase boundary and universality class using the recent developed techniques by the authors.
 Publication:

arXiv eprints
 Pub Date:
 May 1997
 DOI:
 10.48550/arXiv.condmat/9705179
 arXiv:
 arXiv:condmat/9705179
 Bibcode:
 1997cond.mat..5179K
 Keywords:

 Condensed Matter  Strongly Correlated Electrons
 EPrint:
 Latex, stylefile of JPSJ, 14 pages, 21 figures(eps), 3 tables