Charge transfer and antiferromagnetic insulator phase in SrRu1-x Crx O3 perovskites: Solid solutions between two itinerant electron oxides

Abstract

A full range of SrRu1-x Crx O3 perovskite solid solutions (0 <0.3) are itinerant, and ferromagnetic below 160- 190 K, and x>0.7 materials are itinerant and Pauli paramagnetic, but a substantial insulating region is found between these limits. Neutron diffraction shows the x=0.4 material to be antiferromagnetic with a high Néel temperature ∼400 K and a saturated moment of 1.7 μB, despite the large CrRu disorder. A 50 K magnetic transition and a low temperature structural phase change to orthorhombic Imma symmetry have been discovered in SrCrO3, suggesting that the ground state of this simple perovskite is more complex than was previously assumed. © 2006 The American Physical Society.