High intrinsic permittivity in Na_(1/2)Bi_(1/2)Cu_3Ti_4O_(12)

摘要

The electrical properties of Na_(1/2)Bi_(1/2)Cu_3Ti_4O_(12) (NBCTO) ceramics between ～8 and 400 K are electrically inhomogeneous, consisting of semiconducting grains and insulating grain boundaries, similar to isostructural CaCu_3Ti_4O_(12) (CCTO); however, the intrinsic permittivity of NBCTO of ～250 at 10 K is much higher compared to ～110 for CCTO. Possible explanations for this high intrinsic permittivity are discussed.