Incommensurate Magnetic Ordering and Spin-Liquid-Like State in a Triangular Lattice BaVS 3: Neutron Diffraction and Scattering Study

Abstract

We performed powder neutron diffraction and scattering experiments of the \(S = \frac{1}{2}\) triangular lattice system, BaVS 3 , and found magnetic reflections below T X ≃30 K. The propagation vector is determined to be incommensurate (0.226 0.226 0) in the hexagonal index. The ordered moment is roughly estimated to be ∼0.5 µ B /V. Although the elastic magnetic diffractions disappear above T X , low-energy inelastic scattering, which has an Q -ω dispersion similar to that below T X , was observed between T X and the metal-insulator transition point T MI ≃70 K, indicating the presence of a long-range and dynamic antiferromagnetic correlation, i.e., a spin-liquid-like state, between T X and T MI .