NORMAL-STATE NERNST EFFECT OF A HIGH-CRITICAL-TEMPERATURE SUPERCONDUCTOR

We have analyzed the data of Clayhold et al. for the Nernst effect in the normal state of a high critical superconductor, i.e., Tl2Ba2CaCu2O 8+delta. This requested to derive a kinetic expression for the Nernst effect, an expression able to take into account inelastic scattering a nd magnetic-field dependence. This was done along a relaxation time fo rmalism for the solution of the Boltzmann equation but leaving a backg round term which can be calculated by the most appropriate method. The final calculation leads to the evaluation of the background term resu lting from the thermoelectric field-free effect. In order to do this w e have considered a model of Livanov and Sergeev. The Nernst effect is explained by a simple two band model for electrons and holes with dif ferent mobilities. The resulting fit to the experimental data looks ra ther convincing. Several predictions are made thereafter.