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arXiv · 1904.00612

Sequential quantum phase transitions in $J_1$-$J_2$ Heisenberg chains with integer spins ($S > 1$): Quantized Berry phase and valence-bond solids

Shota Fubasami·Tomonari Mizoguchi·Yasuhiro Hatsugai
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Abstract

On the basis of a Berry-phase analysis, we study the ground state of the $J_1$-$J_2$ Heisenberg chain for $S=2,3,4$. We find that changes of the Berry phase occur $S$ times for spin-$S$ systems, indicating the sequential phase transitions. The sequential phase transitions are associated with the change of valence-bond configurations of the ground states. To demonstrate this numerically, we connect the $J_1$-$J_2$ Heisenberg Hamiltonian with the generalized Affleck-Kennedy-Lieb-Tasaki model, and show that the different phases are connected to the different valence-bond-solid states.

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Shota Fubasami, Tomonari Mizoguchi, Yasuhiro Hatsugai. 2019-04-01. Sequential quantum phase transitions in $J_1$-$J_2$ Heisenberg chains with integer spins ($S > 1$): Quantized Berry phase and valence-bond solids. https://doi.org/10.1103/physrevb.100.014438

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