Thermal Conductivity of SrTiO₃, KTaO₃ and BaTiO₃ near the Curie Points

抄録

The thermal conductivity λ near the Curie points of SrTiO₃, KTaO₃ and BaTiO₃ is studied theoretically. The following results are obtained. (1) In SrTiO₃ λ decreases gradually in the high temperature region (about T^−0.5) and has a sharp decrease in the lower temperature side of the Curie point (32 K). (2) In KTaO₃ λ decreases as T⁻¹ in the high temperature side of T_max∼30 K, whereas it decreases sharply in low temperatures, T_max being the temperature of maximum λ. (3) For BaTiO₃ a dip near the Curie point (391 K) in the λ−T curve is derived. These features are in accord with recent experiments.