Combined effect of demagnetization field and magnetic anisotropy on magnetocaloric behavior and magnetocaloric-magnetoresistance correlation in GdTmErCoAl high-entropy amorphous alloy

Abstract The magnetic, magnetocaloric and transport properties were investigated systematically on Gd20Tm20Er20Co20Al20 high-entropy amorphous ribbons with magnetic fields parallel and perpendicular to ribbon surfaces. It is found that the alloy shows greater magnetic entropy change and refrigeration capacity with maximum values of 9.7 J kg−1 K−1 and 551.3 J kg−1 under the perpendicular field change of 5 T, respectively, than those of 8.4 J kg−1 K−1 and 458.1 J kg−1 under the parallel field, respectively. This large difference cannot be simply understood from the demagnetization effect and indicates a significant role of magnetic anisotropy associated with the anisotropy of atomic packing. Besides, magnetoresistance and magnetic entropy change are found to have a power-law correlation with distinct power exponents in different sample orientations with respect to the field. Present results have implications for the understanding and design of amorphous refrigerants with advanced magnetocaloric performance.