Achieving fully compensated ferrimagnetism through two-dimensional CrI3/CrGeTe3 heterojunctions

In addition to altermagnets, fully compensated ferrimagnets are another category of collinear magnetic materials that possess zero-net total magnetic moment and exhibit spin-splitting, making them promising for low-energy spintronics, high-density data storage, and high-sensitivity sensors. Although many methods, such as alloying, external electric field, Janus engineering, ferroelectric field, and spin ordering, have been proposed to achieve fully compensated ferrimagnetism, these approaches either face experimental difficulties or produce a small spin-splitting or are volatile. Here, we propose to form vertical heterostructures by stacking two different but equally magnetized two-dimensional ferromagnetic materials. If an A-type antiferromagnetic ordering is satisfied, a fully compensated ferrimagnet can be formed. This vertical heterostructure approach is insensitive to lattice matching and stacking manner, thus being more conducive to experimental realization. Through first-principles calculations, we verify our proposal with several examples, focusing in particular on CrI3/CrGeTe3 heterojunction composed of experimentally synthesized CrI3 and CrGeTe3 monolayers. The calculations show that CrI3/CrGeTe3 is a fully compensated ferrimagnet, with pronounced spin-splitting, and that tensile strain is more favorable for achieving fully compensated ferrimagnetism. Our work provides an experimentally feasible strategy for realizing fully compensated ferrimagnetism, thereby further advancing the development of this field.