Multicaloric effect in multiferroic sulpho spinel MCr2S4 (M = Fe & Co)

Abstract

We observe a rare occurrence of multiple caloric effects in multiferroic FeCr2S4 & CoCr2S4 compounds having a spinel structure. The significant magnetic entropy changes of ∼3.72 J kg-1 K−1 and 3.99 J kg−1 K−1 are observed in FeCr2S4 & CoCr2S4, respectively, for a magnetic field change of 0–50 kOe at the paramagnetic to ferrimagnetic transition (TN). At TN large magnetoresistances are also observed as ∼17% and ∼10.2% for FeCr2S4 & CoCr2S4, respectively, for applied magnetic field 50 kOe. On the other hand, the electrocaloric entropy are also found considerable as ∼0.56 J-m−3 K−1 and 1.24 J-m−3 K−1 for a small electric field change of 0–100 kV/m at the ferroelectric transition temperature (TC) for CoCr2S4 & FeCr2S4, respectively.