Room-temperature I-V characteristics of a single hollow La₂/₃Ca₁/₃MnO₃ microparticle

In this work we present an electrical characterization of La₂/₃Ca₁/₃MnO₃ particles obtained by spray pyrolysis. We optimized the synthesis conditions to obtain the desired compound with the expected structure and the ferromagnetic transition at the same temperature as the bulk material. We found that a post-deposition thermal treatment enhances the magnetic properties of the samples. The study of structural, morphological and magnetic properties shows that the walls of the hollow spheres are constituted by grains on the nanometer scale. The I-V characterization shows typical signatures of tunneling transport. This behavior can be associated with the grain boundaries within the microparticle's wall acting as tunnel barriers.