Thermal conductivity of perovskite ferroelectrics

Thermal conductivities of BaTiO3, PbTiO3, KNbO3, KTaO3, NaNbO3, and Pb(Mg1/3Nb2/3)O-3 (PMN) single crystals have been measured from 2 to 390 K. Pronounced jumps are found at structural transitions in BaTiO3 and KNbO3. A low-temperature anomaly from soft optical phonons is observed in KTaO3. For PMN and NaNbO3, glasslike behavior is observed in both the thermal conductivity and heat capacity measurements. We associate the glasslike behavior in NaNbO3 with the phase separation phenomena reported in recent studies. (c) 2008 American Institute of Physics.