Interfacial dominated ferromagnetism in nanograined ZnO: a μSR and DFT study

• DOI: 10.1038/srep08871
• Publication Date: 2015-03-09T11:08:38Z
• Authors: Thomas Tietze; Patrick Audehm; Yu–Chun Chen; Gisela Schütz; Boris B. Straumal; Svetlana G. Prota...; Andrey A. Mazilkin; Petr B. Straumal; Thomas Prokscha; Hubertus Luetkens; Zaher Salman; Andreas Suter; Brigitte Baretzky; Karin Fink; Wolfgang Wenzel; Denis Danilov; Eberhard Goering
• Keywords: Diamagnetism; Muon spin spectroscopy; Volume fraction

Abstract Diamagnetic oxides can, under certain conditions, become ferromagnetic at room temperature and therefore are promising candidates for future material in spintronic devices. Contrary to early predictions, doping ZnO with uniformly distributed magnetic ions is not essential obtain samples. Instead, the nanostructure seems play key role, as ferromagnetism was also found nanograined, undoped ZnO. However, origin of primarily non–magnetic like still unexplained a controversial subject within scientific community. Using low energy muon spin relaxation combination SQUID TEM techniques, we demonstrate that volume fraction strongly related sample occupied by grain boundaries. With molecular dynamics density functional theory find coupled electron states Our results provide evidence microscopic model oxides.