Title :
Anomalous low-frequency dispersion in X2BaCuO5 compounds
Author :
Vicente, J.L. ; Razzitte, A.C. ; Cordero, M.C. ; Mola, E.E.
Author_Institution :
Div. Quimica Teorica, INIFTA, La Plata, Argentina
Abstract :
We present and discuss the anomalous low-frequency dispersion process observed in perovskite ceramics (X2BaCuO5, X=Eu-La-Y). The interpretation is given in terms of the Dissado-Hill-Jonscher theory. It is based on a cluster description of the structural ordering and fluctuation in carrier-dominated dielectrics. It is shown that this form of response occurs for systems of low spatial dimensionality and generates a sample-size-dependent conductivity. The relationship of the mechanism to that of power-law noise in electrical systems is identified and its structural interpretation explored. Particular features of several ceramics related to superconductors compounds are described
Keywords :
barium compounds; ceramics; dielectric losses; europium compounds; lanthanum compounds; optical susceptibility; permittivity; yttrium compounds; Dissado-Hill-Jonscher theory; Eu2BaCuO5; La2BaCuO5; Y2BaCuO5; anomalous low-frequency dispersion; carrier-dominated dielectrics; cluster description; complex susceptibility; fractals; perovskite ceramics; sample-size-dependent conductivity; spatial dimensionality; structural ordering; Ceramics; Conductivity; Dielectric constant; Dielectric loss measurement; Dielectric losses; Dielectric measurements; Dielectrics and electrical insulation; Fluctuations; Frequency; Superconductivity;
Conference_Titel :
Electrical Insulation and Dielectric Phenomena, 1997. IEEE 1997 Annual Report., Conference on
Conference_Location :
Minneapolis, MN
Print_ISBN :
0-7803-3851-0
DOI :
10.1109/CEIDP.1997.634585
