Perturbed angular correlation study of Ta-181-doped PbTi1-xHfxO3 compounds


Autoria(s): Alonso, Roberto Emilio; López García, Alberto Raúl; Rubia López, Miguel Ángel de la; Frutos Vaquerizo, José de
Data(s)

01/07/2012

Resumo

In this work, the hyperfine quadrupole interaction at Ta-doped PbTi1-xHfxO3 polycrystalline samples is studied for the first time. Powders with x=0.25, 0.50 and 0.75 were prepared and characterized by X-ray diffraction analysis. Perturbed Angular Correlation (PAC) analyses were done as a function of temperature, using low concentration Ta-181 nuclei as probes. In the ferroelectric and paraelectric phases of these compounds two sites were occupied by the probes. For each site the quadrupole frequency, asymmetry and relative distribution width parameters were obtained as a function of temperature above and below the Curie temperature (T-C). One of these sites was assigned to the regular Ti-Hf site, while the other one was assigned to some kind of defect. The behavior of the hyperfine parameters as a function of temperature was analyzed in terms of a recent published phase diagram and the presence of disorder below and above T-C. For the three compositions measured, the obtained hyperfine parameters present discontinuities which correspond to the ferroelectric-paraelectric phase transition. In both phases it was found broad frequency distributed interactions. The disorder in the electronic distribution would be responsible for the broad line width of the hyperfine interaction. (C) 2012 Elsevier B.V. All rights reserved.

Formato

application/pdf

Identificador

http://oa.upm.es/16538/

Idioma(s)

eng

Publicador

E.T.S.I. Telecomunicación (UPM)

Relação

http://oa.upm.es/16538/1/INVE_MEM_2012_135020.pdf

http://www.sciencedirect.com/science/article/pii/S0921452612003857

info:eu-repo/semantics/altIdentifier/doi/10.1016/j.physb.2012.04.005

Direitos

http://creativecommons.org/licenses/by-nc-nd/3.0/es/

info:eu-repo/semantics/openAccess

Fonte

Physica B: Condensed Matter, ISSN 0921-4526, 2012-07, Vol. 407, No. 13

Palavras-Chave #Telecomunicaciones #Física
Tipo

info:eu-repo/semantics/article

Artículo

PeerReviewed