Title :
A comparative study of Ni2MnGa, Ni2MnAl, and Ni2MnIn Heusler alloy films
Author :
Kim, K.W. ; Kudryavtsev, Y.V. ; Rhee, J.Y. ; Lee, N.N. ; Lee, Y.P.
Author_Institution :
Dept. of Phys., Sunmoon Univ., Asan, South Korea
fDate :
7/1/2004 12:00:00 AM
Abstract :
Ni2MnGa, Ni2MnAl, and Ni2MnIn alloy films were fabricated by using a flash-evaporation technique. A wide substrate temperature range (from 150 K to 720 K) was chosen to prepare the alloy films with significantly different atomic ordering. Various physical properties, including optical properties, were investigated. It was found that the optical properties of the bulk alloys are very sensitive to the atomic ordering. Unexpectedly, the disordered alloy films are not ferromagnetically ordered. The Ni2MnAl bulk alloy exhibits a nonmagnetic behavior. Annealing of the disordered films restores the ordered structure with an almost full recovery of the magnetic and transport properties of the ordered films. These results were further discussed in connection with the atomic structures of the alloy films.
Keywords :
X-ray diffraction; aluminium alloys; epitaxial layers; gallium alloys; indium alloys; magnetic annealing; manganese alloys; nickel alloys; optical properties; semimetallic thin films; transmission electron microscopy; transport processes; 150 to 720 K; Heusler alloy films; Ni2MnAl; Ni2MnGa; Ni2MnIn; annealing; atomic ordering; ferromagnetically ordered; flash-evaporation technique; magnetic properties; nonmagnetic behavior; optical properties; transport properties; Annealing; Atom optics; Iron alloys; Magnetic films; Magnetic properties; Nickel alloys; Optical films; Optical sensors; Temperature distribution; Temperature sensors; Huesler alloy; Ni–Mn–Al; Ni–Mn–Ga; Ni–Mn–In;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2004.829207
