Tailoring Unusual Ferrimagnetism in Rare-Earth Iron Garnets via Graphene Interlayers.

Abstract

Ferrimagnets (FiMs), particularly compensated FiMs, composing of coupled sublattices with antiparallel and inequivalent magnetic moments, present a unique material platform for the regulation of magnetism, which is highly desirable for the design of next-generation spin-based devices. Nevertheless, highly efficient methods for controlling its ferromagnetism remains significantly limited owning to the epitaxial growth required for producing high quality and fully featured films. This study, demonstrates the multiple tunability of ferrimagnetism in the rare-earth iron garnets (REIG: thulium iron garnet) film by incorpoating the graphene interlayers. Continuous evolution of magnetic anisotropy and an unexpected/tunable magnetization compensation point (T_M) are realized. Through soft X-rays absorption spectroscopy analysis, the presented anisotropic behavior of orbital moments provides direct evidence for the modulation of magnetic anisotropy with large tunability. The large enhancement of the emerged T_M is further confirmed by the temperature-dependent X-ray magnetic circular dichroism signals, which reveal tunable exchange coupling for inequivalent magnetic atoms. These results establish an efficient strategy to tailor the magnetism in low dimensional REIG films through interlayer engineering and advance the study of REIG-based spintronics.