Effect of competing orders on the half-magnetization plateaus in spin-1 and spin-3/2 pyrochlore magnets
Phys. Rev. B 114, 154408 – Published 9 September, 2026
DOI: https://doi.org/10.1103/p2hg-8jxs
Abstract
We use large-scale density-matrix renormalization group simulations with bond dimensions up to to determine the magnetization curves of spin-1 and spin- pyrochlore Heisenberg antiferromagnets. Both models exhibit a robust half-magnetization plateau. On the largest cubic cluster for which controlled energy extrapolations are feasible, containing 64 sites, we find that a plateau state with a 16-site magnetic unit cell (quadrupled structural unit cell) consistently has lower energy than competing ordering patterns for both spin lengths. This contrasts sharply with the prediction of the effective quantum dimer model and suggests a breakdown of the perturbative mechanism at the Heisenberg point. These results provide a nonperturbative characterization of field-induced phases in pyrochlore magnets and predictive guidance for spin-1 and spin- materials.