A method for making oriented thin films of a ternary intermetallic compound having a tetragonal structure and generally uniaxial magnetic, optical, electronic, and mechanical properties, said method comprising the steps of:
- a) selecting a substrate material having an alignment suitable for biasing the orientation of said ternary intermetallic compound and exhibiting no chemical reactiveness to said ternary intermetallic compound;
- b) heating said substrate material to a temperature above 450.degree. C.;
- c) depositing simultaneously a first metal, a second metal, and a third metal on said substrate material to directly produce said thin film of said ternary intermetallic compound, whereby said thin film adopts the L1.sub.0 crystal structure.