First-principles study of Zn-doping effects on phase stability and magnetic anisotropy of Ni-Mn-Ga alloys

0534552 - FZÚ 2021 RIV GB eng J - Journal Article
Janovec, J. - Straka, Ladislav - Sozinov, A. - Heczko, Oleg - Zelený, M.
First-principles study of Zn-doping effects on phase stability and magnetic anisotropy of Ni-Mn-Ga alloys.
Materials Research Express. Roč. 7, č. 2 (2020), s. 1-11, č. článku 026101. E-ISSN 2053-1591
R&D Projects: GA ČR GA16-00043S
Institutional support: RVO:68378271
Keywords : magnetic shape memory alloy * ab initio calculations * doping * phase stability * martensitic transformation * Curie temperature * magnetic anisotropy
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 1.620, year: 2020
Method of publishing: Open access

The effect of Zn doping on Ni-Mn-Ga magnetic shape memory alloy was studied by the firstprinciples calculations using exact muffin-tin orbital method in combination with the coherentpotential approximation and projector augmented-wave method. Trends in martensitic transformation temperature TMand Curie temperature TC were predicted from calculated energy differences between austenite and nonmodulated martensite,ΔEA−NM, and energy differences between paramagnetic and ferromagnetic state,ΔEPM−FM. Doping upon the Ga-sublattice results in stabilization of martensitic phase which indicates the increase in TM. TC is affected only weakly or slightly decreases, becauseΔEPM−FM of martensite does not change significantly with doping. The substitution ofMnatoms by Zn causes the decrease in both TMand TC. Comparing to Cu-doped Ni-Mn-Ga alloys, we predict that doping with Zn results in smaller decrease in TC but also in smaller increase in TM.
Permanent Link: http://hdl.handle.net/11104/0312735