Geometric entanglement and quantum phase transition in generalized cluster-XY models

Aydin Deger*, Tzu-Chieh Wei

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

2 Citations (Scopus)
110 Downloads (Pure)


In this work, we investigate quantum phase transition (QPT) in a generic family of spin chains using the ground-state energy, the energy gap and the geometric measure of entanglement (GE). In many of prior works, GE per site was used. Here, we also consider GE per block with each block size being two. This can be regarded as a coarse grain of GE per site. We introduce a useful parameterization for the family of spin chains that includes the XY models with n-site interaction, the GHZ-cluster model and a cluster antiferromagnetic model, the last of which exhibits QPT between a symmetry-protected topological (SPT) phase and a symmetry-breaking antiferromagnetic phase. As the models are exactly solvable, their ground-state wavefunctions can be obtained, and thus, their GE can be studied. It turns out that the overlap of the ground states with translationally invariant product states can be exactly calculated, and hence, the GE can be obtained via further parameter optimization. The QPTs exhibited in these models are detected by the energy gap and singular behavior of geometric entanglement. In particular, the XzY model exhibits transitions from the nontrivial SPT phase to a trivial paramagnetic phase. Moreover, the halfway XY model exhibits a first-order transition across the Barouch-McCoy circle, on which it was only a crossover in the standard XY model.

Original languageEnglish
Article number326
Number of pages41
JournalQuantum Information Processing
Issue number10
Publication statusPublished - Oct 2019
MoE publication typeA1 Journal article-refereed


  • Quantum entanglement
  • Quantum phase transition
  • Quantum spin chain


Dive into the research topics of 'Geometric entanglement and quantum phase transition in generalized cluster-XY models'. Together they form a unique fingerprint.

Cite this