Large reversible magnetocaloric effect caused by two successive magnetic transitions in ErGa compound

Abstract

Intermetallic compound ErGa exhibits two successive magnetic transitions: spin-reorientation transition at TSR=15 K and ferromagnetic-paramagnetic transition at TC=30 K. Both transitions contribute greatly to the magnetic entropy change (ΔSM), each yielding a significant peak on their ΔSM-T curve and thus a considerable value of refrigerant capacity (RC) without hysteresis loss. For a magnetic field change of 5 T, the maximal values of −ΔSM are 21.3 J/kg K at TC and 16.5 J/kg K at TSR, with an RC value of 494 J/kg. Large reversible magnetocaloric effect and RC indicate the potentiality of ErGa as a candidate magnetic refrigerant at low temperatures.