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arXiv · 1711.00036

Phase transitions of a 2D deformed-AKLT model

Nicholas Pomata·Ching-Yu Huang·Tzu-Chieh Wei
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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.

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Nicholas Pomata, Ching-Yu Huang, Tzu-Chieh Wei. 2018-09-18. Phase transitions of a 2D deformed-AKLT model. https://doi.org/10.1103/physrevb.98.014432

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