Hongping Xiang

Ferrimagnetic and half-metallic CaCu3Fe4O12: Prediction from first principles investigation

The structural stability and physical properties of CaCu3Fe4O12 were studied by the use of the full-potential linearized augmented plane wave method. The authors’ calculated result indicates that the title compound is stable both thermodynamically and mechanically. It is ferrimagnetic and half-metallic. The calculated magnetic structure reveals that the coupling of Cu–Fe is antiferromagnetic, while those of Cu–Cu and Fe–Fe are ferromagnetic.

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

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.

Structural stability and magnetic coupling in CaCu3Co4O12 from first principles

The structural, electronic and magnetic properties of CaCu(3)Co(4)O(12) were studied by use of the full-potential linearized augmented plane wave method. The calculated results indicate that CaCu(3)Co(4)O(12) is stable both thermodynamically and mechanically. Both GGA (generalized gradient approximation) and GGA+U methods predict that CaCu(3)Co(4)O(12) is metallic. The ferromagnetic configuration is only slightly more stable in energy compared with the non-magnetic configuration (3.7xa0meV), suggesting that they are competitive for being the ground state. Co is in the low spin state (S = 1/2).