Giant magnetocaloric effect in GdAlO₃ and a comparative study with GdMnO₃

Abstract

The magnetic properties and magnetocaloric effect of polycrystalline GdAlO 3 and GdMnO 3 have been investigated to assess their potential usage as magnetic refrigerants at cryogenic temperatures. These compounds undergo antiferromagnetic transitions at low temperatures which are associated with the giant magnetic entropy change effect ( − △ S M ) ∼40.9 J Kg · K −1 under a field change of 0–9 T for GdAlO 3 while the moderate effect of 18 J Kg · K −1 is observed for polycrystalline GdMnO 3 . Though the relative cooling power of both the stated materials is similar however, the absence of magnetic and thermal hysteresis makes GdAlO 3 a more efficient magnetic refrigerant than GdMnO 3 .