Magneto-elastic coupling behavior of the double perovskite BaFeMoO.

BaFeMoO has been reported to exhibit a ferromagnetic to a paramagnetic transition with a Curie temperature above room temperature, and thus it is a potential material for spintronics. These exciting properties are related, at least in part, to combined structural and magnetic instabilities. A conventional analysis of lattice parameter data from the present study and literature in terms of spontaneous strain shows that the magnetic ordering is accompanied by a significant volume strain, which implies a strong coupling behavior of magneto-elastic properties in BaFeMoO. In addition, to address the correlation between anti-site defects (ASD) and magnetic properties, we have carried out a comparative study of six cubic BaFeMoO polycrystals with different degrees of ASD. The correlations among the Curie temperature, low-temperature saturation magnetism, and ASD are discussed in detail using a combination of diffraction and magnetic measurements. This systematic study, especially the strain analysis, of BaFeMoO will facilitate its potential applications in the field of spin electronics and thin film engineering.