Magnetic correlations in the triangular antiferromagnet FeGa₂S₄

The crystal structure and magnetic correlations in triangular antiferromagnet FeGa₂S₄ are studied by x-ray diffraction, magnetic susceptibility, neutron diffraction, and neutron inelastic scattering. We report significant mixing at the cation sites and disentangle magnetic properties dominated by ma...

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Detalhes bibliográficos
Autores: Guratinder, K., Schmidt, Martin, Walker, Helen, Bewley, R. I., Wörle, Michael, Cabra, Daniel Carlos, Osorio, Santiago Antonio, Villalba, Martín Emilio, Madsen, A. K., Keller, Lukas, Wildes, Andrew, Puphal, Pascal, Cervellino, Antonio, Rüegg, C., Zaharko, Oksana
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:Argentina
Recursos:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/142313
Acesso em linha:http://sedici.unlp.edu.ar/handle/10915/142313
Access Level:acceso abierto
Palavra-chave:Ciencias Exactas
Física
Crystal structure
Magnetic interactions
Inelastic neutron scattering
Neutron diffraction
Susceptibility measurements
X-ray diffraction
Descrição
Resumo:The crystal structure and magnetic correlations in triangular antiferromagnet FeGa₂S₄ are studied by x-ray diffraction, magnetic susceptibility, neutron diffraction, and neutron inelastic scattering. We report significant mixing at the cation sites and disentangle magnetic properties dominated by major and minor magnetic sites. The magnetic short-range correlations at 0.77 Å⁻¹ correspond to the major sites and being static at base temperature they evolve into dynamic correlations around 30–50 K. The minor sites contribute to the magnetic peak at 0.6 Å⁻¹, which vanishes at 5.5 K. Our analytical studies of triangular lattice models with bilinear and biquadratic terms provide the ratios between exchanges for the proposed ordering vectors. The modeling of the inelastic neutron spectrum within linear spin-wave theory results in the set of exchange couplings J₁ = 1.7, J₂ = 0.9, J₃ = 0.8 meV for the bilinear Heisenberg Hamiltonian. However, not all features of the excitation spectrum are explained with this model.