Thermal conductivity of polycrystalline YBa2Cu3O7−δ in a magnetic field

Abstract

The thermal conductivity of high-purity sintered ${\mathrm{YBa}}_2$ ${\mathrm{Cu}}_3$ ${\mathrm{O}}_{7\mathrm{-}\mathrm{\delta }}$ powder, in both zero magnetic field and a field of 3 T, has been measured at temperatures from 5 to 26 K. There is a reduction in the thermal conductivity when the magnetic field is applied perpendicular to the direction of heat flow. The results are compared with a crude model that assumes the scattering of phonons by magnetic fluxoids.