Lattice-distortion Induced Magnetic Transition from Low-temperature Antiferromagnetism to High-temperature Ferrimagnetism in Double Perovskites A2FeOsO6 (A = Ca, Sr)

• DOI: 10.1038/srep13159
• Publication Date: 2015-08-20T09:56:16Z
• Authors: Y. S. Hou; H. J. Xiang; X. G. Gong
• Keywords: Superexchange; Ferrimagnetism; Magnetism; Lattice (music)

Abstract High-temperature insulating ferrimagnetism is investigated in order to further reveal its physical mechanisms, as well identify potentially important scientific and practical applications relative spintronics. For example, double perovskites such Sr 2 FeOsO 6 Ca are shown have puzzling magnetic properties. The former a low-temperature antiferromagnet while the latter high-temperature ferrimagnet. In understand underlying we frustrated magnetism of A by employing density functional theory maximally-localized Wannier functions. We find lattice distortion enhances antiferromagnetic nearest-neighboring Fe-O-Os interaction, however weakens interactions via Os-O-O-Os Fe-O-Os-O-Fe paths, so therefore responsible for transition from antiferromagnetism decrease 2+ ion radii. Also discussed 5 d 3 -3 superexchange. propose that superexchange intrinsically instead ferromagnetic previously thought. Our work clearly illustrates frustration can be effectively relieved distortion, thus paving way tuning complex yet other –5 (4 ) perovskites.