Electronic structure and lattice dynamics of the magnetic shape-memory alloy Co2NiGa

TitleElectronic structure and lattice dynamics of the magnetic shape-memory alloy Co2NiGa
Publication TypeJournal Article
Year of Publication2010
AuthorsSiewert M, Gruner ME, Dannenberg A, Hucht A, Shapiro SM, Xu G, Schlagel DL, Lograsso TA, Entel P
Journal TitlePhysical Review B
Volume82
Pages064420
Date Published8/20
ISBN Number1098-0121
Accession NumberISI:000281064300005
Keywordsab-initio, augmented-wave method, co-ni-ga, crystal-structures, HEUSLER ALLOYS, invar-alloys, martensitic phase-transition, phonon-dispersion, single-crystals, SITE PREFERENCE
Abstract

In addition to the prototypical Ni-Mn-based Heusler alloys, the Co-Ni-Ga systems have recently been suggested as another prospective materials class for magnetic shape-memory applications. We provide a characterization of the dynamical properties of this material and their relation to the electronic structure within a combined experimental and theoretical approach. This relies on inelastic neutron scattering to obtain the phonon dispersion while first-principles calculations provide the link between dynamical properties and electronic structure. In contrast to Ni2MnGa, where the softening of the TA(2) phonon branch is related to Fermi-surface nesting, our results reveal that the respective anomalies are absent in Co-Ni-Ga, in the phonon dispersions as well as in the electronic structure.

URL<Go to ISI>://000281064300005
DOI10.1103/Physrevb.82.064420