First-principles Study on the Half-metallicity and Magnetism for the Heusler Based Compounds of N_(2-0.5n)O_0.5nKCa (n=0~4)

Abstract

The half-metallicity and magnetism for compounds of the N (2-0.5n) O 0.5n KCa (n = 0~4), which was based on the d 0 Heusler halfmetals of N 2 KCa and O 2 KCa, were investigated by means of first-principles band calculation method. From the calculated total magnetic moments and the density of states, we found that these three compounds have the half-metallicity. The magnetic moments of the N and O atoms in these compounds were considerably increased compared to those of pure N 2 KCa and O 2 KCa. The K atoms have a large negative magnetic moments. The relationship between the value of magnetic moments for each atom and density of states are discussed.