Measurement-Protocol Dependence of the Magnetocaloric Effect in Ni-Co-Mn-Sb Heusler Alloys

In the quest for materials for solid-state refrigeration, proper characterization of magnetocaloric properties is crucial to optimization. In particular, it is important to properly study the irreversible change in the magnetocaloric effect due to the presence of thermal hysteresis, which is commonly overlooked in the literature. This report investigates in detail how the observed adiabatic temperature change in a class of shape-memory Heusler alloys depends on the measurement protocol, by analyzing the temperature- and field-dependent irreversibility of the effect. The results illustrate that the thermal hysteresis should always be taken into account for such compounds.