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Topological effects at short antiferromagnetic Heisenberg chains

Jizhong Lou·Shaojin Qin·Tai-Kai Ng·Zhaobin Su
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Abstract

The manifestations of topological effects in finite antiferromagnetic Heisenberg chains is examined by density matrix renormalization group technique in this paper. We find that difference between integer and half-integer spin chains shows up in ground state energy per site when length of spin chain is longer than $\simξ$, where $ξ\sim\exp(πS)$ is a spin-spin correlation length, for spin magnitude S up to 5/2. For open chains with spin magnitudes $S=5/2$ to S=5, we verify that end states with fractional spin quantum numbers $S'$ exist and are visible even when the chain length is much smaller than the correlation length $ξ$. The end states manifest themselves in the structure of the low energy excitation spectrum.

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Jizhong Lou, Shaojin Qin, Tai-Kai Ng, Zhaobin Su. 2000-06-27. Topological effects at short antiferromagnetic Heisenberg chains. https://doi.org/10.1103/physrevb.65.104401

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