Tuning magnetization compensation temperature of Gd3Fe5O12 epitaxially grown on Gd3Sc2Ga3O12

The compensated ferrimagnetic insulator Gd3Fe5O12 (GdIG) with a magnetization compensation point (T-M similar to 286 K) near room temperature has recently gained significant attention because of its long spin transmission length and absence of Ohmic loss. However, previously reported GdIG films with perpendicular magnetic anisotropy have a T-M far below room temperature, which is unfavorable for practical applications. Here, we show the tuning of T-M from 268 to 303.7 K in perpendicularly magnetized 15 nm GdIG films epitaxially grown on (111) Gd3Sc2Ga3O12 by manipulating the epitaxial strain through controlling the rapid cooling temperature during the annealing process. By varying the film thickness between 5 and 40 nm, the T-M of the film can be further extended to a range of 246-380 K. We have also demonstrated highly efficient switching of the GdIG spin-sublattices driven by current at room temperature in the GdIG/Pt heterostructures with various T-M values, especially with T-M slightly higher than 300 K. Our findings reveal potential opportunities for insulating compensated ferrimagnetic films of GdIG in the development of high-density, high-speed, and energy-efficient spintronic devices.