One-third magnetization plateau in a spin-1 kagome magnet
Phys. Rev. Materials 9, 054408 – Published 27 May, 2025
DOI: https://doi.org/10.1103/PhysRevMaterials.9.054408
Abstract
We investigate the structural and magnetic properties of , focusing on its spin-1 kagome lattice and the intricate coexistence of ferromagnetic (FM) and antiferromagnetic (AFM) interactions. Powder x-ray diffraction analysis confirms a highly crystalline trigonal structure. Detailed Rietveld refinement identifies a single crystallographic Ni site, indicative of a perfect kagome lattice. Magnetic susceptibility measurements suggest predominantly ferromagnetic interactions with an effective magnetic moment consistent with spins, yet the system undergoes AFM ordering at a Néel temperature of 5.8 K. Isothermal magnetization measurements reveal a series of metamagnetic transitions culminating in a plateaulike phase near of the total saturation magnetization. Analysis of the phase boundaries shows that the AFM phase supports a substantial net moment in each kagome layer, comparable with that of the plateau. This observation challenges the conventional model—where a ground state transitions to an up-up-down configuration—commonly assumed for kagome AFMs. Instead, our findings indicate that both the zero-field ground state and the field-induced phases exhibit in-plane ferrimagnetic spin arrangements on the kagome lattice, with the metamagnetic transition corresponding to a shift from layer-by-layer AFM aligned net moments to FM aligned ones. This configuration is stabilized by bond frustration, a network of competing interactions that can favor both FM and AFM couplings, highlighting the essential role of frustration in governing the low-temperature magnetic behavior of spin-1 kagome systems. By moving beyond the canonical paradigm, these results expand the landscape of unconventional magnetic phases and emphasize the intricate interplay between geometry and frustration in kagome lattices.
