Normal-State Transport Properties of Infinite-Layer Sr1−x Lax CuO2 Electron-Doped Cuprates in Optimal-and Over-Doped Regimes

Abstract

Transport properties of electron-doped cuprate Sr1−x Lax CuO2 thin films have been investigated as a function of doping. In particular, optimal-and over-doped samples were obtained by tuning the Sr:La stoichiometric ratio. Optimal-doped samples show a non-Fermi liquid behavior characterized by linear dependence of the resistivity from room temperature down to intermediate temperature (about 150–170 K). However, by approaching temperatures in the superconducting transition, a Fermi-liquid behavior-characterized by a T2-scaling law-was observed. Once established, the transition from a linear-T to a quadratic-T2 behavior was successfully traced back in over-doped samples, even occurring at lower temperatures. In addition, the over-doped samples show a crossover to a linear-T to a logarithmic dependence at high temperatures compatible with anti-ferromagnetic spin fluctuations dominating the normal state properties of electron-doped cuprates.