Two lifetimes in the thermopower of the cuprate metals

TL;DR

This study investigates the thermopower in high-temperature cuprate superconductors, revealing that two distinct relaxation rates influence both magnetotransport and thermoelectric properties, maintaining non-Fermi liquid behavior after irradiation.

Contribution

It demonstrates that two relaxation rates govern the thermopower and magnetotransport in cuprates, linking their anomalous temperature dependencies.

Findings

Thermopower scales with Hall coefficient across temperatures.

Irradiation affects transport conductivities but preserves non-Fermi liquid forms.

Two relaxation rates control both magnetotransport and thermopower.

Abstract

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.