Magnetocaloric effect of high-entropy rare-earth alloy GdTbHoErY

Magnetocaloric effect of a single-phase high-entropy rare-earth alloy GdTbHoErY with the hexagonal close-packed (HCP) structure was studied. As the external field increases, the peak isothermal magnetic entropy change (ΔSM) of the alloy is accompanied by a hump, which widens the ΔSM peak and thus increases the refrigerant capacity (RC) value. Under a magnetic field of 5 T, the RC and the ΔSM reach 453 J kg−1 and 5.4 J kg−1 K−1, respectively. The high RC for the high-entropy alloy is mainly attributed to the wider working temperature range. Moreover, the random distribution of atoms in the lattice leads to a complex magnetic structure and exchange coupling in this alloy. This feature of high-entropy alloy GdTbHoErY makes a gradual change in the magnetic sequence, which leads to an enhanced magnetocaloric effect.