First-principles and molecular dynamics studies on structural, electronic, and magnetic characteristics of (CaC)1/(SiC)1 and (KC)1/(SiC)1 in wurtzite structure.

First-principles density-functional calculations are performed to investigate the electronic structure and magnetic properties of d0 magnetic short-period heterostructures ( MC)1/(SiC)1 (0001) ( M = Ca and K) in wurtzite structure. We found that they are thermodynamically and mechanically stable by the calculations and analyses of formation energies, cohesive energies, and elastic stiffness constants. Moreover, the dynamic stabilities of them were checked from ab initio molecular dynamics. After adding onsite Coulomb repulsion, both (CaC)1/(SiC)1 and (KC)1/(SiC)1 short-period heterostructures are predicted to be magnetic semiconductors. The two carbons per cell couple ferromagnetically and ferrimagnetically for (CaC)1/(SiC)1 and (KC)1/(SiC)1 short-period heterostructures, respectively. [ABSTRACT FROM AUTHOR]