# 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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