Anisotropic dielectric properties in epitaxial Bi3.25La0.75Ti3O12 thin films along different crystal directions

Abstract

Epitaxial (001)-oriented Bi3.25La0.75Ti3O12 (BLT) thin films were grown by pulsed-laser deposition on (001) LaAlO3 single-crystal substrates. The dielectric properties of the BLT films are highly anisotropic along different crystal directions. The dielectric constants are 358 and 160 along [100] and [1(1) over bar 0], respectively. Dielectric nonlinearity is also detected along these crystal directions. On the other hand, a much smaller dielectric constant and no detectable dielectric nonlinearity in a field range of 0-200 kV/cm are observed for a film along [001] where c-axis oriented SrRuO3 is used as the bottom electrode. (C) American Institute of Physics.