1203.1106 (K. Ozdogan et al.)

Robustness and stability of half-metallic ferromagnetism in
alkaline-earth metal mononitrides against doping and deformation    [PDF]

K. Ozdogan, E. Sasioglu, I. Galanakis

We employ ab-initio electronic structure calculations and study the magnetic properties of CaN and SrN compounds crystallizing in the rocksalt structure. These alkaline-earth metal mononitrides are found to be half-metallic with a total spin magnetic moment per formula unit of 1.0 $\mu_B$. The Curie temperature is estimated to be 480 K for CaN and 415 K for SrN well-above the room temperature. Upon small degrees of doping with holes or electrons, the rigid-band model suggests that the magnetic properties are little affected. Finally we studied for these alloys the effect of deformation taking into account both the cases of hydrostatic pressure and tetragonalization keeping constant either the in-plane lattice parameters or the unit cell volume. Even large degrees of deformation only marginally affect the electronic and magnetic properties of CaN and SrN in the rocksalt structure. Finally, we show that this stands also for the zincblende structure. Our results suggest that alkaline-earth metal mononitrides are promising materials for magnetoelectronic applications.

View original: http://arxiv.org/abs/1203.1106