Thermopower in the strongly overdoped region of single-layer Bi2Sr2CuO6+d superconductor

TL;DR

This study investigates how thermoelectric power varies with doping in overdoped Bi2Sr2CuO6+d superconductors, revealing deviations from metallic behavior likely linked to topological changes.

Contribution

It provides detailed analysis of thermopower evolution in overdoped cuprates, highlighting deviations from expected metallic behavior and suggesting topological transitions.

Findings

Thermopower deviates from T-linear behavior in overdoped region.

Deviations increase with higher doping levels.

Proximity to topological change influences thermoelectric properties.

Abstract

The evolution of the thermoelectric power S(T) with doping, p, of single-layer Bi2Sr2CuO6+d ceramics in the strongly overdoped region is studied in detail. Analysis in term of drag and diffusion contributions indicates a departure of the diffusion from the T-linear metallic behavior. This effect is increased in the strongly overdoped range (p~0.2-0.28) and should reflect the proximity of some topological change.