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arXiv · 1412.8177

Lowest-energy states in parity-transformation eigenspaces of SO(N) spin chain

Tigran Hakobyan
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Abstract

We expand the symmetry of the open finite-size SO(N) symmetric spin chain to O(N). We partition its space of states into the eigenspaces of the parity transformations in the flavor space, generating the subgroup $Z_2^{\times(N-1)}$. It is proven that the lowest-energy states in these eigenspaces are nondegenerate and assemble in antisymmetric tensors or pseudotensors. At the valence-bond solid point, they constitute the $2^{N-1}$-fold degenerate ground state with fully broken parity-transformation symmetry.

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Tigran Hakobyan. 2015-07-18. Lowest-energy states in parity-transformation eigenspaces of SO(N) spin chain. https://doi.org/10.1016/j.nuclphysb.2015.07.003

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