Fermi surface and electronic homogeneity of the overdoped cuprate superconductorTl2Ba2CuO6+δas revealed by quantum oscillations

Abstract

We report a quantum oscillation study of ${\text{Tl}}_{2}{\text{Ba}}_{2}{\text{CuO}}_{6+\ensuremath{\delta}}$ for two different doping levels (${T}_{c}=10$ and 26 K) and determine the Fermi-surface size and topology in considerable detail. Our results show that Fermi-liquid behavior is not confined to the edge of the superconducting dome and is robust up to at least $0.3{T}_{c}^{\text{max}}$. Superconductivity is found to survive up to a larger doping ${p}_{c}=0.31$ than in ${\text{La}}_{2\ensuremath{-}x}{\text{Sr}}_{x}{\text{CuO}}_{4}$. Our data imply that electronic inhomogeneity does not play a significant role in the loss of superconductivity and superfluid density in overdoped cuprates, and point toward a purely magnetic or electronic pairing mechanism.