Temperature- and magnetic-field-dependent thermal conductivity of pure and Zn-doped Bi_{2}Sr_{2}CaCu_{2}O_{8+δ} single crystals

Abstract

The thermal conductivity κof Bi-2212 is measured in pure and Zn-doped crystals as a function of temperature and magnetic field. The in-plane resistivity is also measured on the identical samples. Using these data, we make a crude estimate of the impurity-scattering rate Γof the pure and the Zn-doped crystals. Our measurement show that the "plateau" in the κ(H) profile is not observed in the majority of our Bi-2212 crystals, including one of the cleanest crystals available to date. The estimated values of Γfor the pure and Zn-doped samples allow us to compare the κ(H) data with the existing theories of the quasiparticle heat transport in d-wave superconductors under magnetic field. Our analysis indicates that a proper inclusion of the quasiparticle-vortex scattering, which is expected to play the key role in the peculiar behavior of the κ(H), is important for a quantitative understanding of the QP heat transport in the presence of the vortices.

5 pages including 2 eps figures, submitted to Phys. Rev. B. The discussions have been significantly modified. The paper now contains new data sets from samples that are better characterized