Anisotropic low-temperature magnetoresistivity in the normal state of L2−xCexCuO4 single crystals

Abstract

We report in-plane ρab(T, H) and c-axis ρc(T, H) electrical magnetoresistivity measurements on several L2−x CexCuO4 (L=Pr, Sm, Nd) superconducting single crystals. It is found that in the normal state both resistivities ρab(T) and ρc(T) display a minimum at certain temperatures Tminab and Tminc which separates regions of metallic behavior at T>Tmin from semiconducting-like behavior at T<Tmin. In the low-temperature region (T<Tmin), ρab(T) has a logarithmic temperature dependence ρab≈-ln T and negative magnetoresistivity which are argued to be due to 2D localization effects. In contrast, at low temperatures, ρc(T) can be described in terms of a hopping conductivity.