A study of the pressure effect on the Curie temperature in polycrystalline ordered double perovskites was carried out by measuring the temperature dependence of the magnetization in isoelectronic Sr2FeMoO6, Ba2FeMoO6, and Ca2FeMoO6, and in W-substituted Sr2FeMo1-xWxO6 with x=0.70. Pressure up to approximately 10 kbar induces an increase in the Curie temperature in all the samples with different rate: dT(c)/dp results to be 1.7(2) K/kbar for Ba2FeMoO6, 0.60(8) K/kbar for Sr2FeMoO6, 0.25(8) K/kbar for Ca2FeMoO6, and 0.7(1) K/kbar for the W-substituted sample. The results are interpreted in terms of the different lattice structure and cell volume of the investigated systems. A manganitelike model was only partially successful in explaining the observed pressure behavior, thus, pointing out the different nature of the magnetic interaction in doped manganites and in ordered double perovskites.
Pressure effects on the magnetic transition temperature in ordered double perovskites
Di Castro D;Dore P;Postorino P
2008
Abstract
A study of the pressure effect on the Curie temperature in polycrystalline ordered double perovskites was carried out by measuring the temperature dependence of the magnetization in isoelectronic Sr2FeMoO6, Ba2FeMoO6, and Ca2FeMoO6, and in W-substituted Sr2FeMo1-xWxO6 with x=0.70. Pressure up to approximately 10 kbar induces an increase in the Curie temperature in all the samples with different rate: dT(c)/dp results to be 1.7(2) K/kbar for Ba2FeMoO6, 0.60(8) K/kbar for Sr2FeMoO6, 0.25(8) K/kbar for Ca2FeMoO6, and 0.7(1) K/kbar for the W-substituted sample. The results are interpreted in terms of the different lattice structure and cell volume of the investigated systems. A manganitelike model was only partially successful in explaining the observed pressure behavior, thus, pointing out the different nature of the magnetic interaction in doped manganites and in ordered double perovskites.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
