Magnetocaloric effect in Ni _{2.19} Mn _{0.81} Ga Heusler alloys

The results of direct measurements of the magnetic field induced entropy change in the Ni _{2.19} Mn _{0.81} Ga alloy are presented. It is shown that the largest entropy change in the magnetic field 2.6 T is equal to 11 J/kgK. The experimental data are compared with the theoretical results, obtained with the help of the statistical and molecular field theory.