Low-temperature reversible giant magnetocaloric effect in the HoCuAl compound

Abstract

Magnetic properties and magnetocaloric effect (MCE) of the HoCuAl compound is investigated. The compound is found to be ferromagnetic and undergoes a second-order phase transition from ferromagnetic (FM)-to-paramagnetic (PM) state around Curie temperature TC = 11.2 K. A giant MCE is observed and no magnetic hysteresis loss is found. The maximum values of magnetic entropy change (ΔS) are found to be -17.5 J/kg K and -30.6 J/kg K with a refrigerant capacity (RC) value of 178 and 486 J/kg for the field changes of 0-20 kOe and 0-50 kOe, respectively. The large ΔS as well as no hysteresis loss imply HoCuAl a promising candidate for low temperature magnetic refrigerant. © 2013 AIP Publishing LLC.