A theoretical investigation of the special properties of SrFe1−xCoxO3

Using density-functional calculations, we investigate the special properties of SrFe1−xCoxO3. The results show that the ground states have A-type antiferromagnetic order for x = 0.1 and ferromagnetic order for x ≥ 0.2 with Co ions distributed averagely. SrFe1−xCoxO3 exhibits half-metallic nature for 0.2 ≤ x ≤ 0.7 and full-metallic nature for other values of x , and the half-metallic gap decreases with increasing x . The tunneling between the half-metallic ferromagnetic phases drives the large magnetoresistance. In addition, the Co cations are in the intermediate-spin state, while the Fe cations are in the intermediate-spin state for x ≤ 0.5 and the high-spin state for x ≥ 0.6 .