Frequency and temperature dependence of the electrical conductivity of KTaO3; Li and PbTiO3; La, Cu: Indication of a low temperature polaron mechanism

摘要: Abstract Recently, the concept of polarons has again been at focus solid-state research, as it can constitute basis for understanding high-temperature superconductivity or colossal magnetoresistance materials. More than a decade ago there were some indications that play an important role in explaining low temperature maxima imaginary part dielectric constant e ″ ( T ) ABO3 perovskites. In present work we report ac electrical conductivities KTaO3; Li and PbTiO3; La, Cu their frequency dependence. The real complex conductivity was found to follow universal response σ ′ ∝ ν s . A detailed theoretical analysis dependence parameter revealed that, temperatures, tunnelling small is dominating charge transport mechanism