Dielectric properties of bismuth-containing pyrochlores: A comparative analysis

The comparative analysis of the dielectric properties of bismuth-containing pyrochlores with different manifestation of atomic order/disorder was carried out. We examined the dielectric properties (including behavior in electric fields) of two pyrochlore compounds: BZN (presumably a composition close to [Formula: see text][Formula: see text][Formula: see text][Formula: see text] ceramics with chemical disorder in both A and B cation sublattices and Bi₂Ti₂O₇ single crystal with fully chemical ordered structure. The fundamental differences between the dielectric properties of the BZN ceramics and Bi₂Ti₂O₇ single crystal were shown. In particular, in the dielectric relaxation behavior (which cannot be described via Arrhenius law in the Bi₂Ti₂[Formula: see text] or in the influence of the electric fields on the dielectric permittivity (splitting of the field-cooled and zero-field-cooled behaviors was observed for Bi₂Ti₂O₇ below estimated freezing temperature). The results of this study highlights the special role of Bi₂Ti₂O₇ as a candidate material for studying aspects of geometric frustration related with pyrochlore structure in non-magnetic medium and specifies the future directions of research.