Role of stoichiometric and nonstoichiometric defects on the magnetic properties of the half-metallic ferromagnet NiMnSb
2006 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 73, no 6, 064418- p.Article in journal (Refereed) Published
The first material to be predicted from first-principles calculations as half-metallic was NiMnSb, and the research on this material has been intense due to its possible applications in spintronics devices. The failure of many experiments to measure spin polarization to more than a fraction of the predicted 100% has partly been blamed on structural defects. In this work a complete first-principles treatise of point defects, including nonstoichiometric antisites, interstitial and vacancy defects, as well as stoichiometric atomic swap defects in NiMnSb, is presented. We find that the formation energies of the defects span a large scale from 0.2 to 14.4 eV. The defects with low formation energies preserve the half-metallic character of the material. We also find that some of the defects increase the magnetic moment and thus can explain the experimentally observed increase of magnetic moments in some samples of NiMnSb. Most interesting in this respect are Mn interstitials which increase the magnetic moment, have a low formation energy, and keep the half-metallic character of the material.
Place, publisher, year, edition, pages
2006. Vol. 73, no 6, 064418- p.
nickel alloys, manganese alloys, antimony alloys, ferromagnetic materials, ab initio calculations, interstitials, antisite defects, vacancies (crystal), defect states, magnetic moments
IdentifiersURN: urn:nbn:se:liu:diva-35025DOI: 10.1103/PhysRevB.73.064418Local ID: 24646OAI: oai:DiVA.org:liu-35025DiVA: diva2:255873
Björn Alling, Sam Shallcross and Igor Abrikosov, Role of stoichiometric and nonstoichiometric defects on the magnetic properties of the half-metallic ferromagnet NiMnSb, 2006, Physical Review B. Condensed Matter and Materials Physics, (73), 6, 064418.
Copyright: American Physical Society