Electron spin resonance of Gd3+ in the intermetallic Gd1-xYxNi3Ga9 (0 <= x <= 0.90) compounds

Autor(es)

Mendonca, E. C. ^[1] ; Silva, L. S. ^[1] ; Mercena, S. G. ^[1] ; Meneses, C. T. ^[1] ; Jesus, C. B. R. ^{[2, 1]} ; Duque, J. G. S. ^{[2, 1]} ; Souza, J. C. ^[2] ; Pagliuso, P. G. ^[2] ; Lora-Serrano, R. ^[3] ; Teixeira-Neto, A. A. ^[4]

Afiliação do(s) autor(es)

^[1] Univ Fed Sergipe, Programa Posgrad Fis, Campus Prof Jose Aluisio de Campos, BR-49100000 Sao Cristovao, SE - Brazil

^[2] Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP - Brazil

^[3] Univ Fed Uberlandia, Inst Fis, BR-38408100 Uberlandia, MG - Brazil

^[4] Brazilian Ctr Res Energy & Mat CNPEM, Brazilian Nanotechnol Natl Lab LNNano, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Applied Physics; v. 122, n. 16 OCT 28 2017.
• Citações Web of Science: 0

Resumo

In this work, experiments of X-ray diffraction, magnetic susceptibility, heat capacitance, and Electron Spin Resonance (ESR) carried out in the Gd1-xYxNi3Ga9 (0 <= x <= 0.90) compounds grown through a Ga self flux method are reported. The X-ray diffraction data indicate that these compounds crystallize in a trigonal crystal structure with a space group R32. This crystal structure is unaffected by Y-substitution, which produces a monotonic decrease of the lattice parameters. For the x = 0 compound, an antiferromagnetic phase transition is observed at T-N = 19.2 K, which is continuously suppressed as a function of the Y-doping and extrapolates to zero at x approximate to 0.85. The ESR data, taken in the temperature range 15 <= T <= 300 K, show a single Dysonian Gd3+ line with nearly temperature independent g-values. The linewidth follows a Korringa-like behavior as a function of temperature for all samples. The Korringa rates (b = Delta H/Delta T) are Y-concentration-dependent indicating a ``bottleneck{''} regime. For the most diluted sample (x = 0.90), when it is believed that the ``bottleneck{''} effect is minimized, we have calculated the q-dependent effective exchange interactions between Gd3+ local moments and the c-e of < h(f-ce)(2)(q)>(1/2) = 18(2) meV and J(f-ce)(q = 0) = 90(10) meV. Published by AIP Publishing. (AU)

• Processo FAPESP: 12/04870-7 - Estudos de novos materiais complexos e avançados
• Beneficiário: Pascoal Jose Giglio Pagliuso
• Modalidade de apoio: Auxílio à Pesquisa - Temático