Accession Number:

AD1011065

Title:

Structural Disorder and Magnetism in the Spin-Gapless Semiconductor CoFeCrAl

Descriptive Note:

Journal Article

Corporate Author:

Indian Institute of Technology Mandi India

Report Date:

2016-08-24

Pagination or Media Count:

5.0

Abstract:

Disordered CoFeCrAl and CoFeCrSi0.5Al0.5 alloys have been investigated experimentally and by first-principle calculations. The melt-spun and annealed samples all exhibit Heusler-type superlattice peaks, but the peak intensities indicate a substantial degree of B2-type chemical disorder. Si substitution reduces the degree of this disorder. Our theoretical analysis also considers several types of antisite disorder Fe-Co, Fe-Cr, Co-Cr in Y-ordered CoFeCrAl and partial substitution of Si for Al. The substitution transforms the spin-gapless semiconductor CoFeCrAl into a half-metallic ferrimagnet and increases the half-metallic band gap by 0.12 eV. Compared CoFeCrAl, the moment of CoFeCrSi0.5Al0.5 is predicted to increase from 2.01 B to 2.50 B per formula unit, in good agreement with experiment.

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE