Phase transitions and magnetoelectroelastic instabilities in Pb(Fe1/2Nb1/2)O-3 multiferroic ceramics

Autor(es)

Fraygola, B. ^[1] ; Frizon, N. ^[1] ; Lente, M. H. ^[2] ; Coelho, A. A. ^[3] ; Garcia, D. ^[1] ; Eiras, J. A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Dpto Fis, Grp Ceram Ferroeletr GCFerr, BR-13565670 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Paulo, Dept Ciencia & Tecnol, BR-12231280 Sao Jose Dos Campos, SP - Brazil

^[3] Univ Estadual Campinas, LPCM DFA IFGW, Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ACTA MATERIALIA; v. 61, n. 5, p. 1518-1524, MAR 2013.
• Citações Web of Science: 10

Resumo

Magnetoelectric coupling can be observed in multiferroic materials in the regions where magnetic and ferroelectric ordering coexist and in many cases is mediated via lattice strain. Pb(Fe1/2Nb1/2)O-3 (PFN) is a well-known multiferroic, presenting ferroelectric ordering (below T-C = 380 K) and a Neel temperature (antiferromagnetic ordering) T-N = 143 K. However, recent experimental results suggest that PFN can display ferromagnetic ordering at higher temperatures and a still unclear sequence of phase transitions. In this work, high-density PFN ceramics were prepared by a conventional ceramic method. Dielectric, magnetic and anelastic responses were measured as a function of temperature. The experimental results present complementary evidence of anomalies (additional to those which can be directly associated with the reported transitions at T-C and T-N) which cold be associated with a structural phase transition (T similar to 315 K), an antiferromagnetic ferromagnetic phase transition (110 K) and magnetoelectroelastic instabilities around 250 K. (C) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 08/04025-0 - Materiais multifuncionais multiferróicos nanoestruturados: síntese, propriedades, fenomenologia e aplicações
• Beneficiário: José Antonio Eiras
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 10/11187-6 - Determinação do coeficiente de acoplamento magnetoelétrico em materiais multiferróicos monofásicos
• Beneficiário: Barbara Maraston Fraygola
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado