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arXiv · 1010.4273

Critical theory of the topological quantum phase transition in a spin-2 chain

Hong-Chen Jiang·Stephan Rachel·Zheng-Yu Weng·Shou-Cheng Zhang·Zhenghan Wang
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Abstract

We systematically study the phase diagram of S=2 spin chain, by means of density-matrix renormalization group and exact diagonalization methods and confirm the presence of a dimer phase in the AKLT--SZH model. We find that the whole phase boundary between the dimer and SZH phases, including the multicritical point, is a critical line with the same central charge $c=5/2$. Finally, we propose and confirm that this line can be described by the $\rm SO(5)_1$ Wess-Zumino-Witten (WZW) conformal field theory.

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Hong-Chen Jiang, Stephan Rachel, Zheng-Yu Weng, Shou-Cheng Zhang, Zhenghan Wang. 2010-12-06. Critical theory of the topological quantum phase transition in a spin-2 chain. https://doi.org/10.1103/physrevb.82.220403

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