Inverse and enhanced magnetocaloric properties of HoCrO3

We report on the magnetic and magnetocaloric properties of 50% Fe3+ doped polycrystalline HoCrO3 compounds in the vicinity of magnetic transitions. Due to complex magnetic interactions, we do see multiple transitions in χ vs. T graph pertinent to HoCrO3 and HoCr0.5Fe0.5O3 compounds related with Ho3+ ordering, Cr3+ ordering and spin – reorientation (SR). Due to re-orientation of spins, metamagnetic transitions are evident in low field regime of M vs. H. Quantified values of -ΔSM around Ho3+ ordering infer that indeed Fe3+ substitution helped in enhancing magnetocaloric effect of HoCrO3 compound. Such an enhanced -ΔSM values are ascribed to increase in canting of Fe/Cr spins. Present results would be helpful in developing magnetic refrigerant materials for space applications particularly below 30 K