Epitaxial Growth and Magnetic Properties of Mn5(SixGe1-x)3 Thin Films

Structural and magnetic properties of Mn5(SixGe1-x)3 thin films wereinvestigated. Ferromagnetic Mn5Ge3 and anti-ferromagnetic Mn5Si3 thin filmshave been synthesized and characterized as these compounds exhibit interestingfeatures for the development of spintronics. Here, Mn5(SixGe1-x)3 thin filmswere grown on Ge(111) substrates by co-deposition using molecular beam epitaxy.Crystalline thin films can be produced with controlled Si concentrationsranging from 0 to 1. The thin films were relaxed by dislocations at theinterface with the substrate. A lattice parameter variation was observed as theSi content increased, which is comparable to previous works done in bulk.Reflection highenergy electron diffraction diagrams and X-ray diffractionprofiles showed that lattice parameters a and c are shrinking and that thesurface roughness and crystallinity degrade as the Si amount increases.Magnetometric measurements revealed a ferromagnetic behavior for all Siconcentrations. The measured average ferromagnetic moment per manganese atomdecreased from 2.33 to 0.05 μB/Mn atom. No ferro to anti-ferromagnetictransition was observed contrary to the bulk Mn5(SixGe1-x)3 compound.