The temperature dependence of heat capacity of MnSi has been measured in the presence of different values of magnetic field. When the magnetic field is applied, an appreciable adiabatic temperature change is observed in the compound. The entropy change due to isothermal change of magnetic field is found to be significant well above the ordering temperature of the compound. This produces a large refrigerant capacity in MnSi, making it important for applications in refrigeration cycles.

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We report the results of magnetization and heat capacity measurements on the rare-earth intermetallic compound DyPt2 as a function of temperature and magnetic field. These studies reveal the presence of short range magnetic correlations in DyPt2 above the Curie temperature, well inside the paramagnetic regime. This contributes appreciably to the magnetic entropy, which can be tuned with the help of applied magnetic field over a wide range of temperature. As a result, DyPt2 exhibits a large magnetocaloric effect that persists at temperatures much above the Curie temperature.

We have studied the electrical resistivity, magnetization, and heat capacity of the off-stoichiometric Heusler alloys Ni50Mn35In15 and Ni50Mn34.5In15.5 as functions of temperature and magnetic field. The results show that the alloy system is more sensitive to the composition than what is apparent from the established phase diagram. We have found that the ground states as well as the nature of phase transitions strongly depend on concentration differences as low as 0.5 at. %. While in the case of Ni50Mn34.5In15.5 we do observe a magnetic field induced martensite to austenite phase transition, there is no detectable signature of any field induced transition in the Ni50Mn35In15 alloy even up to fields as high as 80 kOe. Accordingly, the functional properties of these two alloys are also drastically different.

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