First-principles investigations of the structural, electronic, and magnetic properties of Cr-doped AlN/GaN (0001) heterostructures reveal the possibility of efficient spin injection from a ferromagnetic GaN:Cr electrode through an AlN tunnel barrier. We demonstrate that Cr atoms segregate into the GaN region and that these interfaces retain their half-metallic behavior leading to a complete, i.e., 100%, spin polarization of the conduction electrons. This property makes the wide band-gap nitrides doped with Cr to be excellent candidates for high-efficiency magnetoelectronic devices.
J. E. Medvedeva et al., "Half-Metallicity and Efficient Spin Injection in AlN/GaN:Cr (0001) Heterostructure," Physical Review Letters, American Physical Society (APS), Jan 2005.
The definitive version is available at http://dx.doi.org/10.1103/PhysRevLett.94.146602
United States. Defense Advanced Research Projects Agency
National Science Foundation (U.S.)
Keywords and Phrases
III-V Semiconductors; Ab Initio Calculations; Magnetic Tunnelling; Semiconductor Heterojunctions; Spin Polarised Transport; Wide Band Gap Semiconductors; Aluminium compounds; Chromium; Ferromagnetic materials; Gallium compounds; Segregation
Article - Journal
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