Abstract
Isotropic spin-1 chains with bond alternation are studied. Analytic (both variational and perturbative) results are presented. A phase transition is found to separate the S=1 Haldane phase and the dimer phase. The critical point is numerically determined using the Binder parameter. The universality class is predicted to be given by the level-1 SU(2) Wess-Zumin-Witten model, and this prediction is supported by the present exact diagonalization study. The dimer phase is found to be connected to the "S=2" Haldane phase in a special limit. The change of the excitation spectra and the string order parameter with bond alternation is discussed.
Original language | English |
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Article number | 014 |
Pages (from-to) | 4895-4920 |
Number of pages | 26 |
Journal | Journal of Physics: Condensed Matter |
Volume | 7 |
Issue number | 25 |
DOIs | |
Publication status | Published - 1995 |
Externally published | Yes |
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics