Dielectric and polarization experiments in high loss dielectrics: a word of caution

Mario Maglione (1) , M. A. Subramanian (2)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 Department of Chemistry

The recent quest for improved functional materials like high permittivity dielectrics and/or multiferroics has triggered an intense wave of research. Many materials have been checked for their dielectric permittivity or their polarization state. In this report, we call for caution when samples are simultaneously displaying insulating behavior and defect-related conductivity. Many oxides containing mixed valent cations or oxygen vacancies fall in this category. In such cases, most of standard experiments may result in effective high dielectric permittivity which cannot be related to ferroelectric polarization. Here we list few examples of possible discrepancies between measured parameters and their expected microscopic origin.

Mots clés: Bismuth compounds; Calcium compounds; Copper compounds; Dielectric losses; Dielectric polarisation; Electrical conductivity; Ferroelectric materials; Lutetium compounds; Permittivity; Tantalum compounds; Vacancies (crystal)

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Mario Maglione, M. A. Subramanian. Dielectric and polarization experiments in high loss dielectrics: a word of caution. Applied Physics Letters, 2008, 93 (3), 032902 (3 p.). ⟨10.1063/1.2949752⟩. ⟨hal-00282783⟩