Magnetocaloric properties of ferrimagnetic TbFeCo thin films near compensation temperature with perpendicular anisotropy: effect of sputtering power

We demonstrate sputtering power dependent magnetic compensation temperatures, perpendicular magnetic anisotropy, and magnetocaloric properties of ferrimagnetic Tb30(Fe7Co63) amorphous thin films. The magnetic compensation temperature rises from 224 K to 407 K when sputtering power increases from 50 W to 100 W. Magnetization, and Hall effect measurements confirm the presence of perpendicular magnetic anisotropy in these films. The out-of-plane magneto-optic kerr effect (MOKE) measurements reveal that the films deposited with 50 W, 70 W, and 80 W exhibit good perpendicular magnetic anisotropy with a squareness ratio of around 1. The effective anisotropy constant (Ku) increases with increase with sputtering power and reaches a maximum value of 1.29 x 106 erg/cm3 at 100 W. Magnetocaloric investigations across a wide temperature range using a +/- 15kOe magnetic field show a substantial increment in magnetic entropy change. The magnetic entropy change is noticed around 0.25 J/kgK for films deposited with 100 W. These findings emphasize the significance of sputtering power in controlling the magnetic properties of amorphous ferrimagnetic thin films for spintronic and magnetocaloric applications.