Giant magnetocaloric effect in Fe-doped rare earth orthochromite GdCr0.5Fe0.5O3

Abstract

In this manuscript, we present investigations into the magnetic and magnetocaloric properties of the Fe-doped orthochromite system GdCr0.5Fe0.5O3, along with its structural, electronic and thermal properties. Manifestations of orbital-mediated electron-phonon coupling, the charge transfer mechanism and exchange splitting can clearly be observed in the acquired Raman and core-level X-ray photoemission spectra. Additionally, Fe substitution enhances Cr3+/Fe3+ spin canting, thereby strengthening the weak ferromagnetic component over the paramagnetic moment of Gd3+, resulting in a suppression of temperature-induced magnetization reversal in the Fe-doped system as compared to the parent GdCrO3. A maximum magnetic entropy change (-Delta Smaxm) of 44.86 J kg-1 K-1, adiabatic temperature change (Delta Tmaxad) of 15.14 K and relative cooling power (RCPmax) of similar to 691.81 J kg-1 for a magnetic field variation of 9 T at cryogenic temperatures were obtained from the temperature-dependent magnetization and heat capacity measurements. These observed giant magnetocaloric effect parameters make this system a promising competitor in the field of magnetic refrigeration technology for cooling applications at cryogenic temperatures.