Magnetic and Structural Properties of Rapidly Quenched Tetragonal Mn Ga Nanostructures
نویسندگان
چکیده
Nanostructured Mn Ga ribbons with and 1.1 were prepared using arc-melting, melt-spinning and annealing. As-spun samples crystallized into hexagonal and cubic Heusler crystal structures based on the concentration of Mn in Mn Ga. Upon vacuum-annealing the samples at 450 C for about 50 hours, both the hexagonal and cubic structures transformed into a tetragonal structure. High-temperature x-ray diffraction and high-temperature magnetometry showed that the samples with low Mn content (Mn Ga and Mn Ga) retain their tetragonal structure up to 850 K but the samples with high Mn concentrations (Mn Ga and Mn Ga) undergo a structural phase transition from tetragonal to hexagonal phases around 800 K. The magnetic properties of Mn Ga ribbons were very sensitive to Mn concentration, where the magnetization and anisotropy energy increased and the coercivity decreased as x increased from 0 to 1.1. Although the Curie temperatures of Mn Ga and Mn Ga samples could not be determined because of the structural phase transition, the Curie temperature decreased with increasing x in Mn Ga. The maximum magnetization of 57 emu/g (300 emu/cm ) and the coercivity of 6.5 kOe were measured in the Mn Ga and Mn Ga ribbons, respectively.
منابع مشابه
Magnetic and Structural Properties of Rapidly Quenched Tetragonal Mn<sub>3-x</sub> Ga Nanostructures
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Magnetic and Structural Properties of Rapidly Quenched Tetragonal Mn3-x Ga Nanostructures
Ga samples could not be determined because of the structural phase transition, the Curie temperature decreased with increasing x in Mn Ga. The maximum magnetization of 57 emu/g (300 emu/cm) and the coercivity of 6.5 kOe were measured in the Mn Ga and Mn Ga ribbons, respectively.
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