By Topic

Growth and magnetic properties of single crystal Co2MnX (X=Si,Ge) Heusler alloys

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

8 Author(s)
S. F. Cheng ; Naval Res. Lab., Washington, DC, USA ; B. Nadgomy ; K. Bussmann ; E. E. Carpenter
more authors

Half-metallic (HM) ferromagnetic materials have recently drawn intense interests due to their potential use in magnetoelectronic devices. Co-based Heusler alloys of the type CO2MnX (X=Si,Ge), predicted to be HM by first principles band structure calculations, are of particular interest since they alone possess Curie temperatures in excess of 900 K. Since the spin polarization (P) is believed to be sensitive to antisite defects that are likely to occur in vapor-quenched thin film synthesis, single crystals of Co2MnX (X=Si, Ge) were prepared using the tri-arc Czochralski method. X-ray diffraction, including Laue backscattering, was employed to determine the high crystalline quality of these crystals. SQUID magnetometry measured a magnetic moment per formular unit that is close to the calculated value indicating that these alloys may in fact be HM. However, point contact Andreev reflection, a technique that has reliably measured high P in CrO2, measures P values for these crystals of 50-60%, well below their theoretical values. The reduced spin polarization may be due to the effects of crystal symmetry breaking at the surface or the presence of anti-site defects, or that these materials are not truly half-metallic

Published in:

IEEE Transactions on Magnetics  (Volume:37 ,  Issue: 4 )