Ferromagnetic and ordered MnSi(111) epitaxial layers

We report a comprehensive study of ordered MnSi films grown on Si111 which provides clear proofs that these MnSi films have the same magnetic and electronic properties of bulk MnSi compound, so closing a long-standing question. Furthermore, our measurements show the presence of a room-temperature ferromagnetic transition consistent with the ferromagnetic ground state predicted for Mn atoms with reduced coordination near surfaces and interfaces of silicon by recent calculations of Hortamani et al. Phys. Rev. B 78, 104402 2008. The possibility of growing layers on semiconductors which are ferromagnetic at room temperature RT is of paramount importance for nonvolatile memories and spintronic devices based on the injection of spin-polarized current from a ferromagnetic metal into a semiconductor. In this perspective MnSi films grown on Si substrates represent an interesting case study.