Ru${}_{2-x}$Mn${}_{1+x}$Al thin films

Abstract

The cubic Heusler alloy Ru${}_{2-x}$Mn${}_{1+x}$Al is grown in thin film form on MgO and MgAl${}_2$O${}_4$ substrates. It is a highly spin-polarised ferrimagnetic metal, with weak magnetocrystalline anisotropy. Although structurally and chemically similar to ${\text{Mn}}_2{\text{Ru}}_x\text{Ga}$, it does not exhibit ferrimagnetic compensation, or large magneto galvanic effects. The differences are attributed to a combination of atomic order and the hybridisation with the group 13 element Al or Ga. The spin polarisation is around 50 to 60 %. There is a gap in the density of states just above the Fermi level in fully ordered compounds.

8 pages , 7 figures, 2 tables