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Numerical Renormalization Approach to Two-Dimensional Quantum Antiferromagnets with Valence-Bond-Solid Type Ground State

Yasuhiro Hieida·Kouichi Okunishi·Yasuhiro Akutsu
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Abstract

We study the ground-state properties of the two-dimensional quantum spin systems having the valence-bond-solid (VBS) type ground states. The ``product-of-tensors'' form of the ground-state wavefunction of the system is utilized to associate it with an equivalent classical lattice statistical model which can be treated by the transfer-matrix method. For diagonalization of the transfer matrix, we employ the product-wavefunction renormalization group method which is a variant of the density-matrix renormalization group method. We obtain the correlation length and the sublattice magnetization accurately. For the anisotropically ``deformed'' S=3/2 VBS model on the honeycomb lattice, we find that the correlation length as a function of the deformation parameter behaves very much alike as that in the S=3/2 VBS chain.

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Yasuhiro Hieida, Kouichi Okunishi, Yasuhiro Akutsu. 1999-01-17. Numerical Renormalization Approach to Two-Dimensional Quantum Antiferromagnets with Valence-Bond-Solid Type Ground State. https://doi.org/10.1088/1367-2630%2F1%2F1%2F007

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