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Lattice dynamics, mechanical stability and electronic structure of Fe-based Heusler semiconductors.

ABSTRACT: The structural and mechanical stability of Fe₂TaAl and Fe₂TaGa alloys along with the electronic properties are explored with the help of density functional theory. On applying different approximations, the enhancement of semiconducting gap follows the trend as GGA < mBJ < GGA + U. The maximum forbidden gaps observed by GGA + U method are E_g = 1.80 eV for Fe₂TaAl and 1.30 eV for Fe₂TaGa. The elastic parameters are simulated to determine the strength and ductile nature of these materials. The phonon calculations determine the dynamical stability of all these materials because of the absence of any negative frequencies. Basic understandings of structural, elastic, mechanical and phonon properties of these alloys are studied first time in this report.

SUBMITTER: Khandy SA

PROVIDER: S-EPMC6365636 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Lattice dynamics, mechanical stability and electronic structure of Fe-based Heusler semiconductors.

Khandy Shakeel Ahmad SA Islam Ishtihadah I Gupta Dinesh C DC Khenata Rabah R Laref A A

Scientific reports 20190206 1

The structural and mechanical stability of Fe2TaAl and Fe2TaGa alloys along with the electronic properties are explored with the help of density functional theory. On applying different approximations, the enhancement of semiconducting gap follows the trend as GGA < mBJ < GGA + U. The maximum forbidden gaps observed by GGA + U method are Eg = 1.80 eV for Fe2TaAl and 1.30 eV for Fe2TaGa. The elastic parameters are simulated to determine the s ...[more]

PMID: 30728387

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