Class of exactly solvable SO(n) symmetric spin chains with matrix product ground states

@article{Tu2008ClassOE,
  title={Class of exactly solvable SO(n) symmetric spin chains with matrix product ground states},
  author={Hong-Hao Tu and Guang-ming Zhang and Tao Xiang},
  journal={Physical Review B},
  year={2008},
  volume={78},
  pages={094404}
}
We introduce a class of exactly solvable SO(n) symmetric Hamiltonians with matrix product ground states. For an odd n >= 3 case, the ground state is a translational invariant Haldane gap spin liquid state; while for an even n >= 4 case, the ground state is a spontaneously dimerized state with twofold degeneracy. In the matrix product ground states for both cases, we identify a hidden antiferromagnetic order, which is characterized by nonlocal string order parameters. The ground-state phase… Expand

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