Multipartite nonlocality and topological quantum phase transitions in a spin-1/2 XXZ model on a zigzag lattice

Multipartite nonlocality is a measure of multipartite quantum correlations. In this paper, we investigate multipartite nonlocality in a spin- $$\frac{1}{2}$$ 1 2 XXZ model on a one-dimensional (1D) infinite-size zigzag lattice. In the ground states, the model can undergo topological-type quantum phase transitions (QPTs) between a singlet dimer (SD) phase and an even-parity dimer (ED) phase. Two nonlocality measures $${\mathcal {S}}_o$$ S o (defined on the odd-bond subchains) and $${\mathcal {S}}_e$$ S e (defined on the even-bond subchains) are used to characterize these topological-type QPTs. Both measures show some kinds of singularity (i.e., a discontinuity of the measure or the divergence of its derivative) in the QPTs. Furthermore, in the SD phase and in the vicinity of critical regions, $${\mathcal {S}}_o$$ S o is relatively large, and in most regions of the ED phase, $${\mathcal {S}}_o$$ S o is nearly zero. Thus, similar to order parameters in traditional phase transitions, $${\mathcal {S}}_o$$ S o is an effective physical quantity to characterize these topological-type QPTs. Scaling behavior of the nonlocality measure is also discussed. Graphical abstract