Antisite defects and magnetoresistance in Sr₂FeMoO₆double perovskite

Abstract

We report a detailed study of the magnetic and magnetotransport properties of Sr2FeMoO6 ceramics having a controlled concentration of antisite (AS) defects. It is found that a high-field differential susceptibility exists in all samples, which increases with AS. Similarly, a high-field magnetoresistivity develops and mimics the differential susceptibility. These observations suggest that antisite defects promote some magnetic frustration. High-resolution electron microscopy studies have allowed observation of the existence of antiphase boundary defects in the Sr2FeMoO6 structure.