10.1007/s40089-019-00289-3

The surface effect on the thermodynamic stability, half-metallic and optical properties of Co2MnGa(001) films: a DFT study

  1. Department of Physics, Hamedan Branch, Islamic Azad University, Hamedan, IR
  2. Department of Physics, Kermanshah Branch, Islamic Azad University, Kermanshah, IR
  3. Physics Department, Bu-Ali Sina University, Hamedan, 65174-4161, IR
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Published in Issue 2019-11-07

How to Cite

Faregh, R. A., Boochani, A., Masharian, S. R., & Jafarpour, F. H. (2019). The surface effect on the thermodynamic stability, half-metallic and optical properties of Co2MnGa(001) films: a DFT study. International Nano Letters, 9(4 (December 2019). https://doi.org/10.1007/s40089-019-00289-3

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Abstract

Abstract In this study, the half-metallic properties, thermodynamic stability and optical parameters of the full-Heusler Co 2 MnGa compound and its four different terminations of Co–Co, Co–Mn, Mn–Ga and Co–Ga from the surface of Co 2 MnGa (001) have been calculated based on the density functional theory (DFT). The results confirm the ferromagnetic half-metallic behavior with a magnetic moment of 4.08 μB\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mu_{\text{B}} $$\end{document} and a gap of 0.32 eV at the Fermi level of Co 2 MnGa bulk phase having a Cu 2 MnAl-type structure. The density of states curves showed that all possible terminations from the Co 2 MnGa (001) surface eliminate the half-metallic behavior except the termination of Mn–Ga case. Moreover, the results indicate that the termination of Mn–Ga with the lowest surface energy is the most stable termination for the application in spintronics. The optical coefficients such as real and imaginary dielectric function, refraction, extinction, energy loss function, optical conductivity and reflections of the bulk and Mn–Ga termination have been calculated and compared.

Keywords

  • DFT,
  • Co2MnGa film surface,
  • Thermodynamic phase diagram,
  • Half-metal,
  • Optical properties

References

  1. Mao et al. (2016) Effect of As and Nb doping on the magnetic properties for quaternary Heusler alloy FeCoZrGe (pp. 1-6) https://doi.org/10.1016/j.jmmm.2015.08.123
  2. Xie et al. (2015) First-principles study of four quaternary Heusler alloys ZrMnVZ and ZrCoFeZ (Z = Si, Ge) (pp. 52-55) https://doi.org/10.1016/j.commatsci.2015.03.010
  3. Vasil’ev et al. (2003) Shape memory ferromagnets https://doi.org/10.1070/PU2003v046n06ABEH001339
  4. Dubowik et al. (2007) Films of Heusler alloys (pp. 583-598)
  5. Singh and Barber (2004) Structural, magnetic, and transport properties of thin films of the Heusler alloy Co2MnSi https://doi.org/10.1063/1.1690868
  6. Picozzi and Continenza (2002) Co2MnX.(X = Si, Ge, Sn). Heusler compounds: an ab initio study of their structural, electronic, and magnetic properties at zero and elevated pressure https://doi.org/10.1103/PhysRevB.66.094421
  7. De Groot et al. (1983) New Class of materials: half-metallic ferromagnets https://doi.org/10.1103/PhysRevLett.50.2024
  8. Oogane (2006) Large tunnel magnetoresistance in magnetic tunnel junctions Co2 MnX (X = Al, Si) Heusler alloys (pp. 834-841) https://doi.org/10.1088/0022-3727/39/5/S09
  9. Kubler and Felser (2012) Berry curvature and the anomalous Hall effect in Heusler compounds https://doi.org/10.1103/PhysRevB.85.012405
  10. Tung and Guo (2013) High spin polarization of the anomalous Hall current in Co-based Heusler compounds https://doi.org/10.1088/1367-2630/15/3/033014
  11. Zhu and Zhao (2017) Anomalous resistivity upturn in epitaxial L21-Co2 MnAl films https://doi.org/10.1038/srep42931
  12. Fujii et al. (1994) Electronic and magnetic properties of X2Mn1-xVxSi (X = Fe and Co) (pp. 1881-1888) https://doi.org/10.1143/JPSJ.63.1881
  13. Hütten et al. (2005) Half-metallic alloys (pp. 241-264) Springer-Verlag
  14. Sakuraba et al. (2006) Direct observation of half-metallic energy gap in Co2 MnSi by tunneling conductance spectroscopy https://doi.org/10.1063/1.2335583
  15. Kudryavtsev et al. (2007) Ferromagnetic resonance in Co2MnGa films with various structural ordering 310(2) (pp. 2271-2273) https://doi.org/10.1016/j.jmmm.2006.10.726
  16. Fecher et al. (2005) Design of magnetic materials: the electronic structure of the ordered, doped Heusler compound Co2Cr1−xFexAl https://doi.org/10.1088/0953-8984/17/46/008
  17. Kübler et al. (1983) Formation and coupling of magnetic moments in Heusler alloys https://doi.org/10.1103/PhysRevB.28.1745
  18. Ökoğlu and Gülseren (2010) Electronic structure of half-metallic ferromagnet Co2MnSi at high-pressure (pp. 321-326) https://doi.org/10.1140/epjb/e2010-00188-0
  19. Boochani et al. (2015) Calculation of half-metal, debye and curie temperatures of Co2VAl compound: first principles study 63(5) https://doi.org/10.1088/0253-6102/63/5/641
  20. Majidi et al. (2017) Effect of point defects on the electronic density states of SnC nanosheets: first-principles calculations (pp. 3209-3215) https://doi.org/10.1016/j.rinp.2017.08.049
  21. Achour et al. (2017) Plasma surface functionalization of boron nitride nano-sheets (pp. 110-115) https://doi.org/10.1016/j.diamond.2017.06.012
  22. Solaymani et al. (2018) The effect of different laser irradiation on rugometric and microtopographic features in zirconia ceramics: study of surface statistical metrics (pp. 180-185) https://doi.org/10.1016/j.jallcom.2018.06.213
  23. Ţălu et al. (2016) Fractal features of carbon–nickel composite thin films 79(12) (pp. 1208-1213) https://doi.org/10.1002/jemt.22779
  24. Ţălu et al. (2016) Microstructure and micromorphology of Cu/Co nanoparticles: surface texture analysis 12(5) (pp. 580-588) https://doi.org/10.1007/s13391-016-6036-y
  25. Ţălu et al. (2016) Microstructure and tribological properties of FeNPs@a-C: H films by micromorphology analysis and fractal geometry (pp. 164-169) https://doi.org/10.1016/j.jiec.2016.08.003
  26. Blaha, P., Schwarz, K., Madsen, G.K.H., Hvasnicka, D., Luitz, J.: WIEN2 k, An augmented plane wave local orbitals program for calculating crystal properties. Austria: Karlheinz Schwarz, Techn. Universit Wien, ISBN 3-9501031-1-2. (2001)
  27. Kresse and Furthmüller (1996) Efficiency of ab initio total energy calculations for metals and semiconductors using a plane-wave basis set (pp. 15-50) https://doi.org/10.1016/0927-0256(96)00008-0
  28. Perdew et al. (1996) Generalized gradient approximation made simple https://doi.org/10.1103/PhysRevLett.77.3865
  29. Skaftouros et al. (2013) Generalized Slater-Pauling rule for the inverse Heusler compounds https://doi.org/10.1103/PhysRevB.87.024420
  30. Jung et al. (2000) Study of the 18-electron band gap and ferromagnetismin semi-Heusler compounds by non-spin-polarized electronic band structure calculations (pp. 113-119) https://doi.org/10.1016/S0166-1280(00)00483-8
  31. Sargolzaei et al. (2006) Spin and orbital magnetism in full Heusler alloys: a density functional theory study of Co2YZ (Y = Mn, Fe; Z = Al, Si, Ga, Ge) https://doi.org/10.1103/PhysRevB.74.224410
  32. Han et al. (2012) Preserving stable 100% spin polarization at (111) heterostructures of half-metallic Heusler alloy Co2VGa with semiconductor PbS https://doi.org/10.1063/1.4759159