Dielectric Properties and Maxwell-Wagner Relaxation of Xompounds ACu₃Ti₄O₁₂ (A=Ca,Bi_2/3,Y_2/3,La_2/3)

Authors

Jianjun Liu, University of Nebraska at Omaha
Chun-Gang Duan, University of Nebraska at OmahaFollow
Wai-Ning Mei, University of Nebraska at OmahaFollow
R. W. Smith, University of Nebraska at OmahaFollow
John R. Hardy, University of Nebraska-LincolnFollow

Date of this Version

2005

Comments

Published in JOURNAL OF APPLIED PHYSICS 98, 093703 (2005). Copyright © 2005 American Institute of Physics. Used by permission.

Abstract

We have studied the frequency and temperature dependences of permittivity and impedance of the compounds ACu₃Ti₄O₁₂ (A=Ca, Bi_2/3, Y_2/3, Las2/3) in the ranges of 10⁻¹–10⁶ Hz and −150–200 °C. All compounds investigated display similar dielectric properties. Specifically, they all have a Debye-like relaxation and their dielectric constants are independent of frequency and temperature over a wide range. They all have two electrical responses in impedance formalism, indicating that there are two distinct contributions. We attribute them to grains and grain boundaries in the ceramic samples and explain the dielectric behaviors by Maxwell-Wagner relaxation arising at the interfaces between grains and their boundaries.