MBE growth of a novel chalcopyrite-type ternary compound MnGeP₂

Novel ternary Mn-containing compound MnGeP₂ has been grown on GaAs and InP substrates using molecular beam epitaxy, in which Mn and Ge were supplied from solid sources and P from a gas source. The films obtained showed XRD pattern characteristic of MnGeP₂. Lattice constants were determined using reciprocal lattice mapping analysis. Films directly grown on GaAs substrate showed three-dimensional grain-growth. By introduction of a Ge buffer layer growth mode became two-dimensional. The magnetization vs. temperature curve showed ferromagnetic properties at room temperature, in conflict with theory which predicts its antiferromagnetism. Presence of secondary phase is discussed.