Electronic Structure and Exchange Bias of a Compensated Ferrimagnet Mn2PtAl

Mn
2
PtAl alloy has been investigated for its electronic structure properties along with structural, magnetic and exchange bias properties. It crystallizes in hexagonal structure with lattice constants of a = b = 4.34 Å, and c = 5.47 Å at room temperature. Theoretical calculations reveal a ferrimagnetic arrangement of the magnetic moments of Mn with a small value of total magnetic moment in good agreement with the experimental magnetization measurements. Magnetization isothermal curves in the ambient of a cooling field H
cool
= 70 kOe, show asymmetric hysteresis with a negative shift along H-direction. The estimated exchange bias in Hcool = 70 kOe is giant (2.73 kOe) at 3 K which is attributed to the unidirectional anisotropy associated with ferromagnetic clusters.