Doping dependence of transport and magnetic properties in La_1−xCa_xVO₃

Abstract

We report temperature dependences of transport and magnetic properties of La_1−xCa_xVO₃ controlled by charge carrier doping (x = 0.0 - 0.5). The system exhibits an insulator-to-metal transition concomitant with an antiferromagnetic-to-paramagnetic transition near x=0.2 with increasing substitution. Disorder effects are found to influence the low-temperature transport properties of both insulating and metallic compositions near the critical concentration. At higher temperature resistivity of the metallic compositions has a T² dependence close to the critical concentration (x=0.2 and 0.3) and thus provides an example of disordered Fermi liquid behaviour near the Mott transition. In contrast, at larger doping (x=0.4 and 0.5) the resistivity exhibits a T^1.5 dependence. The molar susceptibility for the metallic samples indicates substantial enhancements due to electron correlation.