Ab initio calculations and synthesis of the off-stoichiometric half-Heusler phase Ni1-xMn1+xSb
2010 (English)In: JOURNAL OF APPLIED PHYSICS, ISSN 0021-8979, Vol. 108, no 9Article in journal (Refereed) Published
We perform a combined theoretical and experimental study of the phase stability and magnetism of the off-stoichiometric Ni1-xMn1+xSb in the half-Heusler crystal phase. Our work is motivated by the need for strategies to engineer the magnetism of potentially half-metallic materials, such as NiMnSb, for improved performance at elevated temperatures. By means of ab initio calculations we investigate Ni1-xMn1+xSb over the whole composition range 0 andlt;= x andlt;= 1 of Ni replacing Mn and show that at relevant temperatures, the half-Heusler phase should be thermodynamically stable up to at least x=0.20 with respect to the competing C38 structure of Mn2Sb. Furthermore we find that half-Heusler Ni1-xMn1+xSb retains half-metallic band structure over the whole concentration range and that the magnetic moments of substitutional Mn-Ni atoms display magnetic exchange interactions an order of magnitude larger than the Ni-Mn interaction in NiMnSb. We also demonstrate experimentally that the alloys indeed can be created by synthesizing off-stoichiometric Ni1-xMn1+xSb films on MgO substrates by means of magnetron sputtering.
Place, publisher, year, edition, pages
American Institute of Physics , 2010. Vol. 108, no 9
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-63149DOI: 10.1063/1.3476282ISI: 000284270900068OAI: oai:DiVA.org:liu-63149DiVA: diva2:376670
Original Publication: Marcus Ekholm, Petter Larsson, Björn Alling, Ulf Helmersson and Igor Abrikosov, Ab initio calculations and synthesis of the off-stoichiometric half-Heusler phase Ni1-xMn1+xSb, 2010, JOURNAL OF APPLIED PHYSICS, (108), 9, 093712. http://dx.doi.org/10.1063/1.3476282 Copyright: American Institute of Physics http://www.aip.org/2010-12-132010-12-132015-08-19Bibliographically approved