›› 2014, Vol. 23 ›› Issue (8): 87103-087103.doi: 10.1088/1674-1056/23/8/087103

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Investigations of the half-metallic behavior and the magnetic and thermodynamic properties of half-Heusler CoMnTe and RuMnTe compounds:A first-principles study

T. Djaafria, A. Djaafria, A. Eliasa, G. Murtazab, R. Khenatac, R. Ahmedd, S. Bin Omrane, D. Rachedf   

  1. a Department of Physics, Faculty of Science, Dr Tahar Moulay University, 20000 Saida, Algeria;
    b Modeling Laboratory, Department of Physics, Islamia College Peshawar, Pakistan;
    c LPQ3M Laboratory, Department of Physics, Faculty of Science and Technology, Mascara University, 29000 Mascara, Algeria;
    d Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor, Malaysia;
    e Department of Physics and Astronomy, College of Science, King Saud University, P. O. Box 2455, Riyadh 11451, Saudi Arabia;
    f Department of Physics, Faculty of Science, Djillali Liabes University, 22000 Sidi Bel-Abbes, Algeria
  • 收稿日期:2014-01-12 修回日期:2014-02-28 出版日期:2014-08-15 发布日期:2014-08-15

Investigations of the half-metallic behavior and the magnetic and thermodynamic properties of half-Heusler CoMnTe and RuMnTe compounds:A first-principles study

T. Djaafria, A. Djaafria, A. Eliasa, G. Murtazab, R. Khenatac, R. Ahmedd, S. Bin Omrane, D. Rachedf   

  1. a Department of Physics, Faculty of Science, Dr Tahar Moulay University, 20000 Saida, Algeria;
    b Modeling Laboratory, Department of Physics, Islamia College Peshawar, Pakistan;
    c LPQ3M Laboratory, Department of Physics, Faculty of Science and Technology, Mascara University, 29000 Mascara, Algeria;
    d Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor, Malaysia;
    e Department of Physics and Astronomy, College of Science, King Saud University, P. O. Box 2455, Riyadh 11451, Saudi Arabia;
    f Department of Physics, Faculty of Science, Djillali Liabes University, 22000 Sidi Bel-Abbes, Algeria
  • Received:2014-01-12 Revised:2014-02-28 Online:2014-08-15 Published:2014-08-15
  • Contact: G. Murtaza, R. Khenata E-mail:murtaza@icp.edu.pk;khenata_rabah@yahoo.fr

摘要: First-principles spin-polarized density functional theory (DFT) investigations of the structural, electronic, magnetic, and thermodynamics characteristics of the half-Heusler, CoMnTe and RuMnTe compounds are carried out. Calculations are accomplished within a state of the art full-potential (FP) linearized (L) augmented plane wave plus a local orbital (APW+lo) computational approach framed within DFT. The generalized gradient approximation (GGA) parameterized by Perdew, Burke, and Ernzerhof (PBE) is implemented as an exchange correlation functional as a part of the total energy calculation. From the analysis of the calculated electronic band structure as well as the density of states for both compounds, a strong hybridization between d states of the higher valent transition metal (TM) atoms (Co, Ru) and lower valent TM atoms of (Mn) is observed. Furthermore, total and partial density of states (PDOS) of the ground state and the results of spin magnetic moments reveal that these compounds are both stable and ideal half-metallic ferromagnetic. The effects of the unit cell volume on the magnetic properties and half-metallicity are crucial. It is worth noting that our computed results of the total spin magnetic moments, for CoMnTe equal to 4 μB and 3 μB per unit cell for RuMnTe, nicely follow the rule μtot=Zt-18. Using the quasi-harmonic Debye model, which considers the phononic effects, the effecs of pressure P and temperature T on the lattice parameter, bulk modulus, thermal expansion coefficient, Debye temperature, and heat capacity for these compounds are investigated for the first time.

关键词: half-Heusler alloys, half-metallic behavior, magnetism, thermodynamic properties, first principles methods

Abstract: First-principles spin-polarized density functional theory (DFT) investigations of the structural, electronic, magnetic, and thermodynamics characteristics of the half-Heusler, CoMnTe and RuMnTe compounds are carried out. Calculations are accomplished within a state of the art full-potential (FP) linearized (L) augmented plane wave plus a local orbital (APW+lo) computational approach framed within DFT. The generalized gradient approximation (GGA) parameterized by Perdew, Burke, and Ernzerhof (PBE) is implemented as an exchange correlation functional as a part of the total energy calculation. From the analysis of the calculated electronic band structure as well as the density of states for both compounds, a strong hybridization between d states of the higher valent transition metal (TM) atoms (Co, Ru) and lower valent TM atoms of (Mn) is observed. Furthermore, total and partial density of states (PDOS) of the ground state and the results of spin magnetic moments reveal that these compounds are both stable and ideal half-metallic ferromagnetic. The effects of the unit cell volume on the magnetic properties and half-metallicity are crucial. It is worth noting that our computed results of the total spin magnetic moments, for CoMnTe equal to 4 μB and 3 μB per unit cell for RuMnTe, nicely follow the rule μtot=Zt-18. Using the quasi-harmonic Debye model, which considers the phononic effects, the effecs of pressure P and temperature T on the lattice parameter, bulk modulus, thermal expansion coefficient, Debye temperature, and heat capacity for these compounds are investigated for the first time.

Key words: half-Heusler alloys, half-metallic behavior, magnetism, thermodynamic properties, first principles methods

中图分类号:  (Basis sets (LCAO, plane-wave, APW, etc.) and related methodology (scattering methods, ASA, linearized methods, etc.))

  • 71.15.Ap
71.15.Mb (Density functional theory, local density approximation, gradient and other corrections) 74.25.Bt (Thermodynamic properties) 75.50.Gg (Ferrimagnetics)