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Magnetic and structural properties of Ni–Mn–Al thin films are investigated. It is demonstrated that the annealed film shows L21 phase at room temperature. Magnetometry measurements reveal that the annealed film is ferromagnetic and a first order transition in magnetization versus temperature measurement confirms that the martensite to austenite transition occurs around room temperature. Transmission electron microscopy measurements confirm that this structural change occurs just below room temperature. The splitting of Mn 2p3/2 level in x-ray photoelectron spectroscopy core level spectra of the annealed Ni–Mn–Al film, confirms that the origin of magnetism is definitely correlated with the local magnetic moment at the Mn atoms. [ABSTRACT FROM AUTHOR]

We have studied the magnetic behavior of YMn 1− x Fe x O 3 ( x =0 and 0.2) nanoparticles synthesized by conventional solid state reaction method. The as-synthesized nanoparticles were found to have hexagonal phase with P6 3 cm space group confirmed by X-Ray diffraction. The particle size was found to be ~70 nm as confirmed by both X-Ray diffraction and Transmission Electron Microscopy. DC magnetization and memory effect measurements imply that the h-YMnO 3 nanoparticles bear a resemblance to super spin-glass state following de Almeida–Thouless like behavior which is being suppressed by Fe-doping. The Fe-doping in YMnO 3 enhances the antiferromagnetic (AFM) transition temperature T N to ~79 K and induces a new magnetic state due to the surface spins which is realized as diluted antiferromagnet in a field (DAFF) as explored by the thermoremanent and isothermoremanent magnetization measured with different applied magnetic field. [ABSTRACT FROM AUTHOR]