Size Dependent Paramagnetic-Weak Ferromagnetic Transition in La2Cu04-yNanoparticles

摘要

La_2CuO_4 (LCO) is a perovskite oxide material and has been used for wide applications such as gas sensing,1) photocatalytic2), memory resistive3) and it is also based compound of superconductor material.4). The interesting characteristic of LCO is the existence of lattice instability associated with the rotation of Cu-0 octahedron in the structure, allowing the LCO to have several phase transitions, depending on temperature, pressure and also dopant. By varying these conditions, the property of LCO can be controlled. Previously, we have succeeded to fabricate the controlled size of undoped LCO nanoparticles (NPs) by sol-gel method.6) In the present work, we reported:(1)the fabrication of La_2CuO_(4-y) (LCO_(4-y)) NPs by heat treatment in non-oxidizing environment and (2) investigation of its electric and magnetic properties.