Evidence of kinetic-energy-driven antiferromagnetism in double perovskites: a first-principles study of La-doped Sr<SUB>2</SUB>FeMoO<SUB>6</SUB>

Using first-principles density-functional calculations, together with exact diagonalization of Fe-Mo Hamiltonian constructed in a first-principles Wannier-function basis, we studied the electronic structure of La-doped double-perovskite compound Sr2FeMoO6. Our calculation shows stabilization of kinetic-energy-driven antiferromagnetic phase for La-rich compounds, in agreement with the results obtained on the basis of previous model calculations