Nd ordering, cluster formation, and the origin of negative magnetization in NdMn0.8Fe0.2O3+delta

Autor(es)

Pajerowski, D. M. ^[1] ; Escanhoela, Jr., C. A. ^{[2, 3]} ; Haskel, D. ^[2] ; Prisk, T. R. ^[4] ; Frontzek, M. D. ^[1] ; Phelan, D. ^[5] ; Mihalik, Jr., M. ^[6] ; Mihalik, M. ^[6]

Afiliação do(s) autor(es)

^[1] Oak Ridge Natl Lab, Neutron Scattering Div, Oak Ridge, TN 37831 - USA

^[2] Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 - USA

^[3] Brazilian Ctr Res Energy & Mat, Brazilian Synchrotron Light Lab, BR-13083970 Campinas, SP - Brazil

^[4] Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 - USA

^[5] Argonne Natl Lab, Mat Sci Div, Argonne, IL 60439 - USA

^[6] SAS, Inst Expt Phys, Watsonova 47, Kosice - Slovakia

• Tipo de documento: Artigo Científico
• Fonte: Journal of Magnetism and Magnetic Materials; v. 497, MAR 1 2020.
• Citações Web of Science: 0

Resumo

The orthorhombic pseudo-perovskite series NdMn1-xFexO3+delta has negative magnetization, i.e. magnetization directed opposite to an applied field under certain conditions, for x = 0.2 and x = 0.25. We have investigated the microscopic origin of this phenomenon for x = 0.2 by using elastic and inelastic scattering techniques including neutron backscattering, X-ray magnetic circular dichroism at the Mn K and Nd L-2 edges, neutron powder diffraction, and powder inelastic neutron scattering. We find that Nd3+ ions possess zero field ordered moments of 1.6 mu(B) per ion at 1.5 K oriented parallel to the Mn moments. Based upon the neutron diffraction, there is a freezing of magnetic clusters before the long-range order sets in. The Nd crystal field levels shift with temperature due to a molecular field that is 1.1 meV at 1.5 K. These findings are consistent with a magnetic domain/cluster model for the negative magnetization in NdMn0.8Fe0.2O3+delta. (AU)

• Processo FAPESP: 16/24137-3 - Estudo do magnetismo orbital em compostos de perovskita dupla sob condições extremas utilizando técnicas de radiação síncrotron
• Beneficiário: Carlos Augusto Escanhoela Júnior
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado