Journal of the Korean Vacuum Society (한국진공학회지)

The Korean Vacuum Society (한국진공학회)
권호 표지

Electronic Structures and Physical Properties of the Ordered and Disordered $Ni_2$MnGa Alloy Films

  • Kim, K. W. (Department of Physics, Sunmoon University) ;
  • Lee, N. N. (q-Psi & Department of Physics, Hanyang University) ;
  • Y. Y. Kudryavtsev (Institute of Metal Physics) ;
  • Lee, Y. P.
  • Published : 2003.10.01
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Abstract

In this study, the electronic structures and physical properties of Ni$_2$MnGa alloy films and their dependence on the order-disorder structural transitions were investigated. The results show that the ordered films behave nearly the same as the bulk $Ni_2$MnGa alloy, including the martensitic transformation at 200 K. Unexpectedly, the disordering in $Ni_2$MnGa alloy films does not lead to any appreciable magnetic ordering down to 4 K. An annealing of the disordered films restores the ordered structure with an almost full recovery of the magnetic and the transport properties of the ordered $Ni_2$MnGa alloy films. A possible explanation of the disappearance of magnetic moment in the disordered film is given by using the ab initio first-principles electronic-structure calculations.

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References

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