Mn-Ge nanocluster formation vs. diluted magnetic semiconductuor formation

The possible fabrication of spintronic devices based on the Mn-Ge binary system supports extensive investigations on the magnetic properties of Mn-Ge structures. However, the global magnetic signal of a given sample is sometime complex due to the coexistence of several objects of unknown magnetic properties. We report the existence of ferromagnetic Mn-Ge nanoclusters (2-4 nm) containing only 4-6% Mn with a Curie temperature of ∼43.5 K, usually attributed to an 1.2% Mn-rich diluted magnetic semiconductuor.