Low Temperature Thermal Conductivity of High Purity YBa$_{2}$Cu$_{3}$O$_{6.99}$ in the Vortex State

TL;DR

This paper develops a theoretical model for low temperature thermal conductivity in high purity YBa2Cu3O6.99, considering impurity and vortex scattering, and successfully matches experimental data across different magnetic fields.

Contribution

It introduces a comprehensive semiclassical approach that includes vortex-quasiparticle scattering and impurity potential strength as a variable, improving understanding of thermal transport in d-wave superconductors.

Findings

Excellent agreement with experimental data in zero and applied magnetic fields.

Impurity potential strength deviates from traditional limits, indicating intermediate scattering regimes.

Highlights the importance of vortex-quasiparticle interactions in thermal conductivity.

Abstract

The low temperature thermal conductivity of a d-wave superconductor is considered for arbitrary strength of the impurity potential. A random distribution of vortices is included within the usual semiclassical approach. The vortex-quasiparticle scattering is accounted for phenomenologically, in addition to impurity scattering. Application of the theory to recent data on high purity YBa$_{2}$Cu$_{3}$O$_{6.99}$ shows excellent agreement with experiment, both in zero field and in the presence of an applied magnetic field. We find that the strength of the impurity potential required to describe the data deviates qualitatively from either the unitary or Born limits.