Excitations of anisotropic spin-1 chains with matrix product ground state
Abstract
We investigate a large class of antiferromagnetic spin-1 chains with nearest neighbour interaction and exactly known matrix product ground state. The spectrum of low-lying excitations is calculated numerically by DMRG and exact diagonalisation. Spin liquid behaviour with an excitation gap is observed meeting the Haldane scenario. Further, we compare properties of the anisotropic model with the well-known isotropic AKLT model and use the analytical single mode approximation to obtain a quantitative understanding of the excitation gap. The low-lying excited states can be interpreted in terms of a magnon-like elementary excitation.
- Publication:
-
European Physical Journal B
- Pub Date:
- January 2003
- DOI:
- 10.1140/epjb/e2003-00025-7
- arXiv:
- arXiv:cond-mat/0301435
- Bibcode:
- 2003EPJB...31..209B
- Keywords:
-
- PACS. 75.10.Jm Quantized spin models;
- 75.10.Jm;
- Quantized spin models;
- Condensed Matter - Strongly Correlated Electrons
- E-Print:
- 9 pages, 6 figures, accepted for publication in Eur. Phys. J. B, uses svjour.cls