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arXiv · 0904.0550

Topologically distinct classes of valence bond solid states with their parent Hamiltonians

Hong-Hao Tu·Guang-Ming Zhang·Tao Xiang·Zheng-Xin Liu·Tai-Kai Ng
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Abstract

We introduce a general method to construct one-dimensional translationally invariant valence bond solid states with a built-in Lie group $G$ and derive their matrix product representations. The general strategies to find their parent Hamiltonians are provided so that the valence bond solid states are their unique ground states. For quantum integer spin-$S$ chains, we discuss two topologically distinct classes of valence bond solid states: One consists of two virtual SU(2) spin-$J$ variables in each site and another is formed by using two $SO(2S+1)$ spinors. Among them, a new spin-1 fermionic valence bond solid state, its parent Hamiltonian, and its properties are discussed in detail. Moreover, two types of valence bond solid states with SO(5) symmetry are further generalized and their respective properties are analyzed as well.

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Hong-Hao Tu, Guang-Ming Zhang, Tao Xiang, Zheng-Xin Liu, Tai-Kai Ng. 2009-04-03. Topologically distinct classes of valence bond solid states with their parent Hamiltonians. https://doi.org/10.1103/physrevb.80.014401

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