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.
@article{arxiv.2503.11413,
title = {Deconfined quantum criticality in a frustrated Haldane chain with single-ion anisotropy},
author = {Niels T. Pronk and Bowy M. La Rivière and Natalia Chepiga},
journal= {arXiv preprint arXiv:2503.11413},
year = {2025}
}