2007/07/10 by G. Bouzerar, Georges Bouzerar, R. Bouzerar +3 · 13 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Antiferromagnetism #Condensed matter physics #Coupling (piping) #Ferromagnetism #Magnet #Magnetic and transport properties of perovskites and related materials #Materials science #Phase (matter) #Phase transition #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Spins #Superexchange #cond-mat.dis-nn #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.76.144419
published in Physical Review B 76(14) (American Physical Society) · 6 figures, submitted to Phys. Rev
arxiv created 2007/07/10 · openalex publication_date 2007/10/15 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We argue, in contrast to recent studies, that the antiferromagnetic superexchange coupling between nearest neighbor spins does not fully destroy the ferromagnetism in dilute magnets with long-ranged ferromagnetic couplings. Above a critical coupling, we find a canted ferromagnetic phase with unsaturated moment. We have calculated the transition temperature using a simplified local random phase approximation procedure which accounts for the canting. For dilute magnetic semiconductors, such as GaMnAs, using ab initio couplings allows us to predict the existence of a canted phase and provides an explanation for the apparent contradictions observed in experimental measurements. Finally, we compared with previous studies that used Ruderman-Kittel-Kasuya-Yosida couplings and reported nonferromagnetic states when the superexchange is too strong. Even in this case the ferromagnetism should remain essentially stable in the form of a canted phase.