Positive Hall coefficient observed in single-crystal Nd 2 − x Ce x CuO 4 − δ at low temperatures

摘要: The Hall coefficient {ital R}{sub H}} has been measured in superconducting single crystals of Nd{sub 2{minus}{ital x}}Ce{sub x}}CuO{sub 4{minus}{delta}}({ital x}{similar to}0.15). Although is sample dependent sign above {similar to}100 K, it increases steeply to positive} values all studied below to}80 K. remains T} (temperature) at 2 contrast the resistivity {rho}{sub a}} which saturates a constant 30 Using two-band model, we account for observed profiles vs and T}. analysis reveals that scattering processes electronlike holelike bands have vastly different temperature scales. hole-scattering rate question whether hole or electron quasiparticles are responsible superconductivity 4{minus}{delta}} discussed.