Navegação Ciências Exatas e da Terra por Assunto "Compostos de cobalto"

Resultados 1-9 de 9

    • Interdependence between training and magnetization reversal in granular Co-CoO exchange bias systems 

      Menéndez Dalmau, Enric; Dias, Thiago; Geshev, Julian Penkov; López-Barberá Martín, José Francisco; Nogués Sanmiquel, Josep; Steitz, Roland; Kirby, Brian J.; Borchers, Julie A.; Pereira, Lino Miguel da Costa; Vantomme, A.; Temst, Kristiaan (2014) [Artigo de periódico]
      The interdependence between training and magnetization reversal in granular Co-CoO exchange bias (EB) systems prepared byOion implantation inCo thin films is demonstrated by polarized neutron reflectometry. While high-fluence ...

    • Pressure and chemical substitution effects in the local atomic structure of BaFe2As2 

      Granado, E.; Ferreira, Leticie Mendonca; Garcia, Flávio; Azevedo, Gustavo de Medeiros; Fabbris, Gilberto Fernandes Lopes; Bittar, Eduardo Matzenbacher; Adriano, C.; Garitezi, T. M.; Rosa, P. F. S.; Bufaiçal, L. F.; Avila, M. A.; Terashita, H.; Pagliuso, P. G. (2011) [Artigo de periódico]
      The effects of K and Co substitutions and quasihydrostatic applied pressure (P < 9 GPa) in the local atomic structure of BaFe2As2, Ba(Fe0.937Co0.063)2As2 and Ba0.85K0.15Fe2As2 superconductors were investigated by extended ...

    • Pressure-induced self-insertion reaction in CoSb/sub 3/ 

      Kraemer, Airton Carlos; Gallas, Marcia Russman; Jornada, Joao Alziro Herz da; Perottoni, Claudio Antonio (2007) [Artigo de periódico]
      The thermoelectric material CoSb3, with skutterudite structure, was subjected to high pressures using a diamond anvil cell up to 40 GPa. Above 20 GPa this compound undergoes an irreversible isosymmetric transition to a ...

    • Rotatable anisotropy driven training effects in exchange biased Co/CoO films 

      Dias, Thiago; Menéndez Dalmau, Enric; Liu, Haoliang; Van Haesendonck, Christian; Vantomme, A.; Temst, Kristiaan; Schmidt, Joao Edgar; Giulian, Raquel; Geshev, Julian Penkov (2014) [Artigo de periódico]
      The training effect for exchange bias in field-cooled Co/CoO bilayers films is investigated. Previous experiments on the same system have shown that, starting from the ascending branch of the first hysteresis loop, coherent ...

    • Structural and spectroscopic investigation of the charge-ordered, short-range ordered, and disordered phases of the Co3O2BO3 ludwigite 

      Galdino, Carlos William; Freitas, Daniele; Medrano, Cynthia Paola Contreras; Sánchez, D. R.; Souza, Rodolfo Tartaglia; Rabello, L. P.; Mendonça, Alberto Aguiar; Ghivelder, Luis; Continentino, Mucio Amado; Zapata, Maximiliano Jesús Moreno; Pinheiro, Carlos Basílio; Azevedo, Gustavo de Medeiros; Rodríguez-Velamazán, J. A.; Garbarino, Gaston; Núñez-Regueiro, M.D.; Granado, E. (2021) [Artigo de periódico]
      Charge ordering is prone to occur in crystalline materials with mixed-valence ions. It is presumably accompanied by a structural phase transition, with possible exceptions in compounds that already present more than one ...

    • A study of the structural, magnetic, and electrical properties of Ba1-xNaxCoO3 compounds (x = 0.25, 0.5, 0.75) 

      Estrada-Rodríguez, Carlos A.; Lopes, Lutiene Fernandes; Lopes, Rovan Fernandes; Mesquita, Fabiano; Turatti, Águeda Maria; Pimentel Junior, Jorge Luiz; Sandoval-Gutiérrez, Santiago; Parra Vargas, Carlos Arturo (2021) [Artigo de periódico]
      Cobaltite-like materials having metal-insulator transitions are relevant in the consumer electronics market. In this work, we present the structural, magnetic, and electrical properties of Ba1-xNaxCoO3(with x= 0.25, 0.5, ...

    • Suppression of magnetic ordering in quasi-one-dimensional FexCo1−xNb2O6 compounds 

      Sarvezuk, Paulo Willian Carvalho; Kinast, Eder Julio; Colin, C. V.; Gusmao, Miguel Angelo Cavalheiro; Cunha, Joao Batista Marimon da; Isnard, Olivier (2011) [Artigo de periódico]
      We present a systematic investigation of the series of compounds FexCo1−xNb2O6 by means of x-ray and neutron powder diffraction combined with magnetic measurements, carried out in the paramagnetic as well as in the ordered ...

    • The magnetization of epitaxial nanometric CoFe2O4(001) layers 

      Rigato, Franco; Geshev, Julian Penkov; Skumryev, Vassil; Fontcuberta Griño, Josep (2009) [Artigo de periódico]
      We have studied the magnetic anisotropy of nanometric CoFe2O4 (CFO) thin films grown on (100) SrTiO3 (STO) substrates. It has been found that epitaxial substrate-induced compressive strain makes the normal-to-film axis ...

    • Tuning the ferromagnetic-antiferromagnetic interfaces of granular Co-CoO exchange bias systems by annealing 

      Menéndez Dalmau, Enric; Modarresi, Hiwa; Dias, Thiago; Geshev, Julian Penkov; Pereira, Lino Miguel da Costa; Temst, Kristiaan; Vantomme, A. (2014) [Artigo de periódico]
      The low-temperature magnetic behavior of granular Co-CoO exchange bias systems, prepared by oxygen ion implantation in Co thin films and subsequent annealing, is addressed. The thermal activation effects lead to an O ...