Magnetic and magneto-optical properties of Mn5(Ge(sub 1-x)M(sub x))3 alloys with M = Sn, Pb

Intermetallic alloys such as Mn5(GeM)3, where M is Sn or Pb, are experimentally investigated to determine the magnetic and magneto-optic properties. The alloys exhibit ferromagnetic ordering at temperatures less than 300 K. The hexagonal phase describes the structure of Mn5(GeSn)3. The Curie temperature and the magnetization are extremely high and are associated with room temperature polar Kerr rotation.