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arXiv · 1904.12493

Reentrance of Topological Phase in Spin-1 Frustrated Heisenberg Chain

Yuan Yang·Shi-Ju Ran·Xi Chen·Zhengzhi Sun·Shou-Shu Gong·Zhengchuan Wang·Gang Su
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Abstract

For the Haldane phase, the magnetic field usually tends to break the symmetry and drives the system into a topologically trivial phase. Here, we report a novel reentrance of the Haldane phase at zero temperature in the spin-1 antiferromagnetic Heisenberg model on sawtooth chain. A partial Haldane phase is induced by the magnetic field, which is the combination of the Haldane state in one sublattice and a ferromagnetically ordered state in the other sublattice. Such a partial topological order is a result of the zero-temperature entropy due to quantum fluctuations caused by geometrical frustration.

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Yuan Yang, Shi-Ju Ran, Xi Chen, Zhengzhi Sun, Shou-Shu Gong, Zhengchuan Wang, Gang Su. 2019-04-29. Reentrance of Topological Phase in Spin-1 Frustrated Heisenberg Chain. https://doi.org/10.1103/physrevb.101.045133

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