Determination of temperature-dependent thermal conductivity of a BaSnO3-δ single crystal by using the 3ω method

The single crystal of the electron doped BaSnO3-delta system has been recently found to have high electrical mobility (up to 320 cm(2)V(-1) s(-1)) at room temperature and excellent oxygen stability. Although thermal conductivity (kappa) of the BaSnO3-delta single crystal is an important physical quantity, the kappa measurement by the conventional DC method has been difficult due to the limited crystal size. Herein, we report the first measurement of kappa by using the 3 omega method from similar to 20 to 300K in the oxygen deficient BaSnO3-delta single crystal with carrier concentration of similar to 10(18) cm(-3). We found that kappa is proportional to T-1 above 50K, indicating that phonons mainly contribute to the heat transport. Moreover, the electronic contribution is determined as similar to 4% of the measured kappa from the Wiedemann-Franz law. The kappa value is 0.132Wcm(-1) K-1 at room temperature and is increased progressively at lower temperatures, becoming overall larger than that of the SrTiO3 single crystal. Our results thus point out that BaSnO3-delta can be a good substrate for growing transparent electronic thin films with the perovskite structure. (C) 2014 Elsevier B.V. All rights reserved.