title: Evolution of Fe magnetic order in NdFexGa ₁- xO₃.
abstract: The evolution of the crystal structure and magnetic properties with Fe content in NdFe(x)Ga(1 - x)O(3) has been studied by magnetization, ac-susceptibility, x-ray and neutron scattering techniques for x ≥ 0.2 in order to determine the phase diagram of the series. X-ray diffraction shows that the crystallographic structure of NdFe(x)Ga(1 - x)O(3) can be described in the space group Pbnm for all x values. Both the magnetic ordering and spin reorientation temperatures of the Fe magnetic sublattice decrease with iron concentration due to the presence of magnetic vacancies occupied by Ga. The long-range Fe magnetic ordering disappears for x ≤ 0.3, while ac-susceptibility measurements evidence the presence of short-range Fe ordered clusters and superspin-glass-like effects for x well below the percolation threshold. The magnetic structure of the compounds, including the spin reorientation temperature range, is determined by high-resolution neutron diffraction analysis. Although the presence of finite magnetic clusters for x values close to percolation is evidenced, the study of a percolation quantum phase transition in this series is hindered by the presence of Nd magnetic moments and a sizeable distribution of composition Δx around the nominal value.
authors.affiliation: Instituto de Ciencia de Materiales de Aragón and Departamento de Física de la Materia Condensada, Universidad de Zaragoza-CSIC, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Parra-Borderías
authors.forename: F
authors.initials: F
authors.lastname: Bartolomé
authors.forename: J A Rodríguez
authors.initials: JA
authors.lastname: Velamazán
authors.forename: J
authors.initials: J
authors.lastname: Bartolomé