Magnetic and magnetocaloric properties of Gd-doped Mn-Ni-Sn alloys

Abstract

In this study, we have investigated the magnetic and magneto-structural transition in Mn-rich Mn2NiSn off-stoichiometric Heusler alloys by introducing Gd separately in the place of Mn and Ni. The structural transition temperature is found to change significantly due to the addition of Gd. Although Gd carries a very large moment as compared to the transition metal elements, the magnetocaloric properties are found to drop drastically where Mn are replaced by Gd. The reason of such observation is the weakening of antiferro coupling between the inter-site Mn atoms in the martensitic phase, which in turn diminishes the sensitivity of the magneto-structural transition.