A comprehensive review of exchange bias effect in Heusler alloys

Magnetic Heusler alloys have been found to be stable above the room temperature which make it suitable for making magnetic based devices. Exchange biasing associated with the ferromagnetic and antiferromagnetic phase in Heusler alloys used in spintronic devices such as spin valves and spin switches. Shift in the hysteresis loop from the origin gives the extent of exchange biasing. Compensated ferrimagnetism has revealed in several half-Heusler alloys which showed the giant exchange biased effect due to the interaction between ferrimagnetic cluster and compensated host associated with the anti-site disorder. In this report, effect of microstructure, temperature, strain, heat treatment, microstructural, grain size, substitution and doping, interface, dependency of size of spin cluster on the level of exchange biasing have been separately discussed in brief mostly in Ni-Mn based half and full-Heusler alloys. Moreover, transformation from body centred cubic to face centred cubic lattice have also elaborated. Role of richness of elements from their conventional stoichiometry of Heusler alloys has significantly been focused. Entropy has been found to be increased as we move from stoichiometric to non-stoichiometric composition in Heusler alloys. Therefore, this article is focused mainly on exchange biased effect in Heusler based magnetic alloys.