Probing the involvement of non-magnetic Sr ion in the ferromagnetic transition of SrRuO3, using XAFS

Abstract

Recent calculations by Maiti et al. have shown that non-magnetic ions like Sr/Ca in Sr/Ca ruthenates may not be mere spectators in the magnetic transitions but their strong hybridization with O atoms may modify the magnetic ground state by distorting the Ru-O-Ru bond angle. Our XAFS results at Sr and Ru K-edges on SrRuO3 indeed demonstrate that the Debye Waller factor for the Sr-coupled bonds viz. Sr-Sr evolve most significantly across the ferromagnetic transition, almost replicating the magnetization curve while the Ru-octahedra evolves only gradually. This clearly establishes the definite role of Sr disorder in the ferromagnetic transition. © 2009 IOP Publishing Ltd.