Epitaxial (Mn0.7Cr0.3)2As and (Fe0.7Mn0.3)2As thin films: Structural and magnetic properties

Abstract We have grown (Mn 0.7 Cr 0.3 ) 2 As and (Fe 0.7 Mn 0.3 ) 2 As thin films directly on Si (1 0 0) substrate by molecular beam epitaxy at the substrate temperature, T S =300 °C. We found that the crystal structure of (Mn 0.7 Cr 0.3 ) 2 As and (Fe 0.7 Mn 0.3 ) 2 As thin films was the tetragonal Mn 2 As type with the lattice constants of a= 3.745 and 3.70A, respectively. (Mn 0.7 Cr 0.3 ) 2 As thin film shows spin-glass behaviour below 130 K, while (Fe 0.7 Mn 0.3 ) 2 As alloy has ferrimagnetic ordering at above room temperature.