The effect of disorder and magnetic properties of nanosized Fe2MnAl Heusler alloy has been studied using a combination of x-ray diffraction, F57e Mössbauer spectroscopy, and dc magnetization. X-ray diffraction spectrum of as-milled sample shows texturing in (400) plane. Mössbauer and dc magnetization studies of milled sample show direction dependent magnetic properties. Hysteresis loop at room temperature taken after the field cooling shows a horizontal shift evidencing the presence of exchange bias. This is attributed to core-shell ferromagnetic-antiferromagnetic coupling within nanoparticles of the same material.

Temperature and field dependent spin polarized electron momentum distributions in ternary Heusler compound Co2MnSi have been measured using the magnetic Compton spectrometer at SPring-8, Japan. The experimental magnetic Compton profile at 10 K reconciles well with the theoretical profile computed using the spin polarized relativistic (SPR) Korringa–Kohn–Rostoker (KKR) method. The temperature and field dependent experimental magnetic profiles have been mainly analyzed to check the role of Mn 3d electrons in the formation of magnetic moments in Co2MnSi. The diffuse contribution from conduction electrons is antiferromagnetically coupled to the spin moment arising from 3d electrons of Co and Mn. The spin moments calculated using SPR-KKR calculations are in good agreement with the present measurements.

No abstract

No abstract

No abstract