A first-principles study of the different magnetoresistance mechanisms in CaCu3Mn4O12 and LaCu3Mn4O12

Abstract

The electronic structure of CaCu₃Mn₄O₁₂ and LaCu₃Mn₄O₁₂ was investigated using a full-potential linearized augmented plane wave method within the Generalized Gradient Approximation (GGA). The ferrimagnetic and ferromagnetic states in these two compounds were investigated and the calculated spin magnetic moments were found to be close to the available experimental values. Calculations of spin polarization for these two oxides show that the ferrimagnetic configurations are the energetically favored ground state, which is consistent with experimental observation. The calculations predict that CaCu₃Mn₄O₁₂ is a semiconductor and that LaCu₃Mn₄O₁₂ is a half-metallic material. Furthermore, the relevance of these different electronic structures to the magnetoresistance is discussed.