Is Heusler compound Co2CrAl a half-metallic ferromagnet:: Electronic band structure, and transport properties

We report the electronic band structure, and transport properties of the Heusler compound Co2CrAl. The band structure calculation shows that Co2CrAl is a true half-metallic ferromagnet with a magnetic moment of 3 mu(B) per formula, characterized by a full indirect band gap of 0.475 eV at around the Fermi level in the minority-spin band. The electronic resistivity shows a power-law T-3.15 temperature dependence at low temperatures ascribed to the unconventional one-magnon scattering processes. A negative MR maximum of -0.33% is obtained for CO2CrAl at 300 K. (C) 2003 Elsevier B.V. All rights reserved.