TRANSPORT-PROPERTIES OF RARE-EARTH-DOPED LA2-XSRXCUO4

We present measurements of the resistivity, the thermopower, and the t hermal conductivity of rare earth (RE) doped La2-xSrxCuO4. Pronounced anomalies occur at the low temperature structural phase transition sho wing that the electronic properties as well as the lattice dynamics de pend strongly on small structural changes. OUT results indicate that a suppressed phonon heat transport is a characteristic feature of La2Cu O4 based superconductors. A possible relationship to the presence of s tripe correlations of holes and spins in doped La2CuO4 is discussed.