Magnetic dynamics in NiTiO3 honeycomb antiferromagnet using neutron scattering
Srimal Rathnayaka, Luke Daemen, Tao Hong, Songxue Chi, Stuart Calder, John A. Schneeloch, Yongqiang Cheng, Bing Li, Despina Louca
Published: 2025/8/30
Abstract
The ilmenite NiTiO3 consists of a buckled honeycomb lattice, with the Ni spins aligned ferromagnetically in-plane and antiferromagnetically out-of-plane. Using neutron spectroscopy, the magnetic structure and the dynamics were investigated as a function of temperature. Dispersive acoustic bands and nearly dispersionless optical bands at ~3.7 meV are described by a highly anisotropy Heisenberg model with stronger antiferromagnetic (AFM) out-of-plane, weaker ferromagnetic (FM) in-plane interactions and an anisotropy gap of 0.95 meV. The order parameter yields a critical exponent between the Heisenberg and two-dimensional Ising models, consistent with highly anisotropic Heisenberg systems. The frustration parameter ~ 2 supports a weakly frustrated system.