High-temperature thermal conductivity of ferroelectric and antiferroelectric perovskites

We report thermal conductivity (κ) above 300 K for perovskite ferroelectrics BaTiO3 (T c ≈ 402 K) and PbTiO3 (763 K), as well as antiferroelectrics PbZrO3 (503 K) and PbHfO3 (476 and 433 K). BaTiO3 and PbTiO3 show similar κ in the paraelectric phase. In contrast, smaller and glasslike κ is found above T c for PbZrO3 and PbHfO3, signifying the presence of large anharmonic distortions in the paraelectric phase. Low-temperature heat capacity on PbZrO3 shows a lack of glasslike thermal behavior in the antiferroelectric phase.