2025/02/19 by C Duffy, Duffy, C. M., S. J. Tu +17 · 1 citation
Chemistry · Physics and Astronomy · #Advanced Condensed Matter Physics #FOS: Physical sciences #Inorganic Fluorides and Related Compounds #Physics of Superconductivity and Magnetism #Strongly Correlated Electrons (cond-mat.str-el) #Superconductivity (cond-mat.supr-con)
paper · pdf · doi:10.48550/arxiv.2502.13612
openalex publication_date 2025/02/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In conventional, phonon-mediated superconductors, the transition temperature Tc and normal-state scattering rate 1/τ - deduced from the linear-in-temperature resistivity ρ(T) - are linked through the electron-phonon coupling strength λ\rm ph. In cuprate high-Tc superconductors, no equivalent λ has yet been identified, despite the fact that at high doping, α - the low-T T-linear coefficient of ρ(T) - also scales with Tc. Here, we use dc resistivity and high-field magnetoresistance to extract τ-1 in electron-doped La2-xCexCuO4 (LCCO) as a function of x from optimal doping to beyond the superconducting dome. A highly anisotropic inelastic component to τ-1 is revealed whose magnitude diminishes markedly across the doping series. Using known Fermi surface parameters and subsequent modelling of the Hall coefficient, we demonstrate that the form of τ-1 in LCCO is consistent with scattering off commensurate antiferromagnetic spin fluctuations of variable strength λ\rm sf. The clear correlation between α, λ\rm sf and Tc then identifies low-energy spin-fluctuations as the primary pairing glue in electron-doped cuprates. The contrasting magnetotransport behaviour in hole-doped cuprates suggests that the higher Tc in the latter cannot be attributed solely to an increase in λ\rm sf. Indeed, the success in modelling LCCO serves to reinforces the notion that resolving the origin of high-temperature superconductivity in hole-doped cuprates may require more than a simple extension of BCS theory.