Ferromagnetic materials that have Curie temperatures above room temperature, crystal structures and lattice matching compatible with compound semiconductors, and high spin polarizations show great promise for integration with semiconductor spintronics. Heusler alloys have crystal structures (fcc) and lattice parameters similar to many compound semiconductors, high spin polarization at the Fermi level, and high Curie temperatures. These properties make them particularly attractive for injectors and detectors of spin-polarized currents. This review discusses the progress and issues related to integrating full and half Heusler alloys into ferromagnetic compound semiconductor heterostructures.
Chris Palmstrøm is a professor of chemical engineering and materials science at the University of Minnesota in Minneapolis. His research emphasizes the growth and characterization of novel electronic and magnetic materials, including ferromagnetic elements and compounds on III–V semiconductors by molecular-beam and chemical-beam epitaxy. He received a PhD degree in electrical and electronic engineering (1979) and spent a postdoctoral year at the University of Leeds. After spending four years as a research associate in the Department of Materials Science and Engineering at Cornell University (1980–1985) and 10 years at Bellcore as a member of technical staff (1985–1994), he joined the faculty at the University of Minnesota. He is a fellow of the American Physical Society and the American Vacuum Society and is a member of the Materials Research Society, APS, AVS, the Minerals, Metals and Materials Society, the Böhmische Physical Society, and IEEE. He is the author of more than 150 publications and one patent on materials growth and characterization.
Palmstrøm can be reached at the University of Minnesota, 421 Washington Ave. SE, Minneapolis, MN 55455, USA; tel. 612–625–7558, fax 612–626–7246, and e-mail email@example.com.