INVESTIGADORES
ALONSO Roberto Emilio
artículos
Título:
The orthorhombic to tetragonal phase transition in Bi1.75Te0.25SrNb1.75Hf0.25O9
Autor/es:
R. E. ALONSO; A.P. AYALA; A. CASTRO; J.J. LIMA SILVA; A. LÓPEZ GARCÍA; A.R. PASCHOAL
Revista:
JOURNAL OF PHYSICS CONDENSED MATTER
Editorial:
IOP PUBLISHING LTD
Referencias:
Año: 2004 vol. 16 p. 4139 - 4148
ISSN:
0953-8984
Resumen:
Abstract
The necessity to produce materials with better performances than those
observed in ferroelectric perovskites has generated the creation of new oxides,
especially those belonging to the Aurivillius family. In the last few years much
attention has been paid to the study of these materials, and this has opened up
newfields due to their basic and applied properties. In this contribution a Raman
analysis and a hyperfine study by perturbed angular correlations spectroscopy
of Bi1.75Te0.25SrNb1.75Hf0.25O9 were carried out to reveal information about
the lattice and the electronic structure. By the use of these techniques, it was
observed that the ferroelectric to paraelectric phase transition at about 570 K
is driven by a soft mode, and the broadening of the dielectric constant as a
function of temperature previously observed at TC is connected to disorder in
the Bi/TeO layer.1.75Te0.25SrNb1.75Hf0.25O9 were carried out to reveal information about
the lattice and the electronic structure. By the use of these techniques, it was
observed that the ferroelectric to paraelectric phase transition at about 570 K
is driven by a soft mode, and the broadening of the dielectric constant as a
function of temperature previously observed at TC is connected to disorder in
the Bi/TeO layer.TC is connected to disorder in
the Bi/TeO layer.