Two lifetimes in the thermopower of the cuprate metals

We study the temperature-dependence of thermoelectric transport in proton-irradiated thin films of the high Tc cuprate Tl2212. All the anomalous transport conductivities are affected by the irradiation but maintain their non-Fermi liquid forms. We note however that the anomalous temperature dependence of the thermopower scales precisely with the temperature dependent Hall coefficient. This provides strong evidence that the two relaxation rates observed to control magnetotransport are also responsible for the anomalous temperature dependence of the thermopower.