Triggering a Metal-insulator Transition in La 0.8 Sr 0.2 MnO 3 Nanoparticle-decorated Carbon Nanotubes

We have studied the magnetic and the electric properties of La0.8Sr0.2MnO3 (LSMO) nanoparticle-decorated carbon nanotubes (CNTs). The magnetic susceptibility showed a paramagnetic - superparamagnetic phase transition at T-sp similar to 200 K with a blocking temperature of T-B similar to 120 K, which can be attributed to the LSMO nanoparticles. At T-sp, the charge transport taking place through the CNTs network showed a metal-insulator transition (MIT) characteristic of the LSMO nanoparticles, indicating a concomitant MIT in the CNTs triggered by the LSMO nanoparticles. In the metallic phase, the charge transport appears to be dominated by a 2D weak localization effect, which at temperatures below T-B was seen to be somewhat suppressed by the internal field. At temperatures below 50 K, a Kondo effect dominates the electric and the magnetic properties.