Very low chemical disorder in epitaxial NiMnSb films on GaAs(111)B

Single-crystalline NiMnSb(111) films with negligibly low defect levels have been grown epitaxially on GaAs(111)B using molecular beam epitaxy and characterized by nuclear magnetic resonance. In a film with only 1% deviation from stoichiometry, 1.1% of all Mn atoms is involved in planar defects, similar to0.5% of all Sb sites is occupied by As-Sb substitutional atoms, and similar to0.2% of all Sb atoms has a modified environment. Both the average concentration of defects and the interface orientation are compatible with maintaining a half-metallic band structure at the ferromagnet/semiconductor interface, making these films a good candidate for spin injection into a semiconductor. (C) 2003 American Institute of Physics.