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Critical Properties of Spin-1 Antiferromagnetic Heisenberg Chains with Bond Alternation and Uniaxial Single-Ion-Type Anisotropy

Wei Chen·Kazuo Hida·Bryan C. Sanctuary
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Abstract

One dimensional S=1 antiferromagnetic Heisenberg chains with bond alternation and uniaxial single-ion-type anisotropy are studied by numerical exact diagonalization of finite size systems. We calculate the ground state phase diagram using the twisted boundary condition method for $D\geq 0$. The ground states of this model contain the Haldane state, large-D state and the dimer state. Using conformal field theory and the level spectroscopy method, we calculate the D and $δ$-dependence of the Luttinger liquid paraments K and the critical exponent $ν$ of the energy gap.

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Wei Chen, Kazuo Hida, Bryan C. Sanctuary. 2008-09-07. Critical Properties of Spin-1 Antiferromagnetic Heisenberg Chains with Bond Alternation and Uniaxial Single-Ion-Type Anisotropy. https://doi.org/10.1143/ptps.138.527

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