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arXiv · 2503.11413

Deconfined quantum criticality in a frustrated Haldane chain with single-ion anisotropy

Niels T. Pronk·Bowy M. La Rivière·Natalia Chepiga
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Abstract

We report a phase diagram of the antiferromagnetic spin-1 chain with nearest-neighbor Heisenberg and three-site interactions in the presence of single-ion anisotropy. We show that the Gaussian and Ising transitions that separate the topological Haldane phase from the two anisotropic phases eventually fuse into a higher symmetry point characterized by the Wess-Zumino-Witten (WZW) SU(2)$_2$ critical theory providing a lattice realization of the conformal embedding. On the other side of the WZW multi-critical point, the Ising critical line reappears together with the eight-vertex transition. This transition is a one-dimensional realization of a deconfined quantum criticality separating the dimerized and Ising antiferromagnetic phases - two ordered phases with incompatible order parameters.

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Niels T. Pronk, Bowy M. La Rivière, Natalia Chepiga. 2025-03-14. Deconfined quantum criticality in a frustrated Haldane chain with single-ion anisotropy. https://doi.org/10.1103/s53y-qmr4

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