Investigation of the magnetic and magnetocaloric properties in metamagnetic REFe2Si2 (RE = Pr and Nd) compounds

The crystal structure, cryogenic magnetic and magnetocaloric properties in NdFe2Si2 and PrFe2Si2 compounds have been investigated. The NdFe2Si2 and PrFe2Si2 crystallized in the body-centered tetragonal structure with the space group of I4/mmm, and underwent first order magnetic transition from paramagnetic to antiferromagnetic (PM - AFM) around Néel temperatures TN of 8.5 K and 15.5 K, respectively. Under an applied-field change of ΔH = 5 T, the maximum values of magnetic entropy change (−ΔSMmax) are 6.4 J/kg·K and 12.4 J/kg·K for PrFe2Si2 and NdFe2Si2, corresponding to relative cooling power (RCP) values of 0.8 J/cm3 and 1.0 J/cm3, respectively. Moreover, under low applied field change and at low temperatures, the PrFe2Si2 and NdFe2Si2 show an inverse MCE because of the existence of the AFM ordering, while under high external magnetic field change, a normal reversible MCE is observed, which is caused by first-order magnetic transition from antiferromagnetic (AFM) to ferromagnetic (FM) state.