Large magnetocrystalline anisotropy in tetragonally distorted Heuslers: A systematic study

Y. I. Matsushita*, G. Madjarova, J. K. Dewhurst, S. Shallcross, C. Felser, S. Sharma, E. K.U. Gross

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

54 Scopus citations

Abstract

With a view to the design of hard magnets without rare earths we explore the possibility of large magnetocrystalline anisotropy energies in Heusler compounds that are unstable with respect to a tetragonal distortion. We consider the Heusler compounds Fe2YZ with Y = (Ni, Co, Pt), and Co2YZ with Y = (Ni, Fe, Pt) where, in both cases, Z = (Al, Ga, Ge, In, Sn). We find that for the Co2NiZ, Co2PtZ, and Fe2PtZ families the cubic phase is always, at T = 0, unstable with respect to a tetragonal distortion, while, in contrast, for the Fe2NiZ and Fe2CoZ families this is the case for only 2 compounds - Fe2NiGe and Fe2NiSn. For all compounds in which a tetragonal distortion occurs we calculate the magnetocrystalline anisotropy energy (MAE) finding remarkably large values for the Pt containing Heuslers, but also large values for a number of the other compounds (e.g. Co2NiGa has an MAE of -2.38 MJ m-3). The tendency to a tetragonal distortion we find to be strongly correlated with a high density of states (DOS) at the Fermi level in the cubic phase. As a corollary to this fact we observe that upon doping compounds for which the cubic structure is stable such that the Fermi level enters a region of high DOS, a tetragonal distortion is induced and a correspondingly large value of the MAE is then observed.

Original languageAmerican English
Article number095002
JournalJournal Physics D: Applied Physics
Volume50
Issue number9
DOIs
StatePublished - 1 Feb 2017
Externally publishedYes

Bibliographical note

Publisher Copyright:
© 2017 IOP Publishing Ltd.

Keywords

  • Heusler compunds
  • ab initio calculations
  • tetragonal distortion

Fingerprint

Dive into the research topics of 'Large magnetocrystalline anisotropy in tetragonally distorted Heuslers: A systematic study'. Together they form a unique fingerprint.

Cite this