Phase transitions of a 2D deformed-AKLT model

Abstract

We study spin-2 deformed-AKLT models on the square lattice, specifically a two-parameter family of $O(2)$-symmetric ground-state wavefunctions as defined by Niggemann, Klümper, and Zittartz, who found previously that the phase diagram consists of a Néel-ordered phase and a disordered phase which contains the AKLT point. Using tensor-network methods, we not only confirm the Néel phase but also find an XY phase with quasi-long-range order and a region adjacent to it, within the AKLT phase, with very large correlation length, and investigate the consequences of a perfectly factorizable point at the corner of that phase.

Major revision during review process; includes several elucidations and creation of Appendices B and E

References in corpus (6)

• Tensor renormalization group approach to 2D classical lattice models
• Accurate determination of tensor network state of quantum lattice models in two dimensions
• Tensor-entanglement renormalization group approach to 2D quantum systems
• Assessing the accuracy of projected entangled-pair states on infinite lattices
• Emergence of the XY-like phase in the deformed spin-3/2 AKLT systems
• Holographic encoding of universality in corner spectra

Cited by in corpus (5)

• Demonstrating the AKLT spectral gap on 2D degree-3 lattices
• AKLT models on decorated square lattices are gapped
• Some aspects of Affleck-Kennedy-Lieb-Tasaki models: tensor network, physical properties, spectral gap, deformation, and quantum computation
• Finite-size scaling analysis of two-dimensional deformed Affleck-Kennedy-Lieb-Tasaki states
• Deformations of the Boundary Theory of the Square Lattice AKLT Model