Magnetothermal properties and magnetocaloric effect in ErFe2 compound

摘要

Magneto-thermal properties and magnetocaloric effect of ErFe2 have been studied. Molecular field theory has been applied on ErFe2 to calculate the magnetization and the magnetic contribution to the heat capacity and entropy. Our calculation shows that ErFe2 is a ferrimagnetic compound with a compensation temperature of around 475 K and a Curie temperature of 596 K. Applying magnetic field to ErFe2 induces canting in moments of the Er sublattice. Density functional theory, as implemented in Wien(2)k code, was used to evaluate the density of states at Fermi energy to calculate the electronic contribution of heat capacity and entropy. We used available values of the shear and bulk moduli to evaluate the Debye temperature in order to calculate the lattice contribution to the heat capacity and entropy. We calculated the magnetocaloric quantities, namely isothermal magnetic entropy change (Delta S-m)(iso) and adiabatic temperature change Delta T-ad, for magnetic fields up to 6 T and temperatures up to 800 K. For an applied field change of 6 T, (Delta S-m)(iso) was found to be ?0.23 J/mole K, while the maximum inverse magnetocaloric effect was found to be approximate to 0.13 J/mole K. The maximum adiabatic change vertical bar Delta T-ad vertical bar(maxis) approximate to 0.5 K per Tesla.