Effect of Fe substitution on the structural, magnetic and electron-transport properties of half-metallic Co2TiSi

Authors

Y. Jin, University of Nebraska - Lincoln
J. Waybright, University of Nebraska - Lincoln
P. Kharel, University of Nebraska - Lincoln
I. Tutic, University of Northern Iowa
J. Herran, University of Northern Iowa
P. Lukashev, University of Northern Iowa
S. Valloppilly, University of Nebraska - LincolnFollow
D. J. Sellmyer, University of Nebraska - LincolnFollow

ORCID IDs

J. Waybright

Date of this Version

2017

Citation

AIP Advances 7, 055812 (2017)

Comments

© 2017 Author(s).

Open access

https://doi.org/10.1063/1.4974281

Abstract

The structural, magnetic and electron-transport properties of Co₂Ti_1-xFe_xSi (x = 0, 0.25, 0.5) ribbons prepared by arc-melting and melt-spinning were investi- gated. The rapidly quenched Co₂Ti_0.5Fe_0.5Si crystallized in the cubic L2₁ structure whereas Co₂Ti_0.75Fe_0.25Si and Co₂TiFe₀Si showed various degrees of B2-type disorder. At room temperature, all the samples are ferromagnetic, and the Curie tem- perature increased from 360 K for Co₂TiSi to about 800 K for Co₂Ti_0.5Fe_0.5Si. The measured magnetization also increased due to partial substitution of Fe for Ti atoms. The ribbons are moderately conducting and show positive tempera- ture coefficient of resistivity with the room temperature resistivity being between 360 μΩcm and 440 μΩcm. The experimentally observed structural and magnetic prop- erties are consistent with the results of first-principle calculations. Our calculations also indicate that the Co₂Ti_1􏰀-xFe_xSi compound remains nearly half-metallic for x ≤ 0.5. The predicted large band gaps and high Curie temperatures much above room temperature make these materials promising for room temperature spintronic and magnetic applications.