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Real-Space Renormalization Group Study of Effects of Anisotropy on S=1 Random Antiferromagnetic Chain

Shigeru Koikegami·Synge Todo·Hajime Takayama
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Abstract

We investigate S=1 antiferromagnetic quantum spin chain, whose exchange couplings are strongly disordered. By the real-space renomalization group method, introduced by Ma, Dasgupta, and Hu, the renormalization group flows are analyzed numerically in a plain of the anisotoropy of the exchange coupling vs. the staggered magnetic field. As the result, the Heisenberg point, which has a zero average of the exchange coupling anisotropy, is specified as the unstable fixed point against the anisotropy.

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Shigeru Koikegami, Synge Todo, Hajime Takayama. 2001-06-21. Real-Space Renormalization Group Study of Effects of Anisotropy on S=1 Random Antiferromagnetic Chain. https://arxiv.org/abs/cond-mat/0106289

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