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arXiv · 1310.4551

Topological nature of magnetization plateaus in periodically modulated quantum spin chains

Haiping Hu·Chen Cheng·Zhihao Xu·Hong-Gang Luo·Shu Chen
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Abstract

We unveil nontrivial topological properties of zero-temperature magnetization plateau states in periodically modulated quantum spin chains under a uniform magnetic field. As positions of plateaus are uniquely determined by the modulation period of exchange couplings, we find that the topologically nontrivial plateau state can be characterized by a nonzero integer Chern number and has nontrivial edge excitations. Our study clarifies the topological origin of the well-known phenomena of quantized magnetization plateaus in one-dimensional quantum spin systems and relates the plateau state to the correlated topological insulator.

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Haiping Hu, Chen Cheng, Zhihao Xu, Hong-Gang Luo, Shu Chen. 2014-08-21. Topological nature of magnetization plateaus in periodically modulated quantum spin chains. https://doi.org/10.1103/physrevb.90.035150

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