THERMAL CONDUCTIVITY AND GRAIN SIZE OF CERAMIC Lal.sSr0.2CuO 4

V. BEKERIS; J. TALPE; M. NUÑEZ REGUEIRO; M.T. MALACHEVSKY; C.D'OVIDIO; D. SERAFINI

SOLID STATE COMMUNICATIONS

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 1990 vol. 75 p. 243 - 245

0038-1098

In order to study the important of Casimir phonon scattering on the thermal conductivity of Lal.sSr0.2CuO4, we measure the thermal conductivity between 1 and 30 K on samples of different grain sizes. We conclude that it starts to be important in this temperature range for grain sizes d < 10#m. The other phonon scattering mechanisms to understand the thermal conductivity temperature dependence are scattering against stacking faults or twin walls and tunnelling systems analogous to those found in glasses.