The dielectric properties of polycrystalline bismuth-based pyrochlores of the general chemical form Bi2(B2+2/3B5+4/3)O 7 and Bi2(B3+5+B5+)O7 where B2+ = Mg, Cu, Zn and Ni, B3+ = Sc and In, and B5+ = Nb and Ta, were investigated as a function of temperature and frequency. At low temperatures (T ∼ 100-150 K), a dielectric dispersion was universally observed within these systems. The dielectric dispersion was analyzed using phenomenological models often used for describing dipolar glass systems. Similar activation energies and pre-exponential damping frequencies are found to exist with dipolar glasses such as RADP (RbxH2PO4-(NH4)1-xH 2PO4), K1-xLixTaO3, KBr1-xCNx and KI1-x(NO2)x.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Materials Chemistry