Prediction of monolayer <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>Fe</mml:mi><mml:msub><mml:mi mathvariant="normal">P</mml:mi><mml:mn>4</mml:mn></mml:msub></mml:mrow></mml:math> with intrinsic half-metal ferrimagnetism above room temperature
Fanjunjie Han, Xu Yan, Fei Li, Hong Yu, Wenjing Li, Xin Zhong, Aitor Bergara, Guochun Yang
Abstract
The design of high-temperature ferrimagnetic materials is highly demanded for next-generation functional spintronic devices. Here, we propose that the combination of nonmetallic structural units and magnetic atoms is an effective way to achieve high-temperature magnetism in two-dimensional (2D) materials. The predicted $\mathrm{Fe}{\mathrm{P}}_{4}$ monolayer, consisting of quasisquare ${\mathrm{P}}_{4}$ units, shows intrinsic half-metal ferrimagnetism above room temperature. Each Fe atom is coordinated with four P atoms associated with the surrounding four quasisquare ${\mathrm{P}}_{4}$ units. First-principles calculations suggest that the $\mathrm{Fe}{\mathrm{P}}_{4}$ monolayer presents a Curie temperature of 460 K. More interestingly, the itinerant electrons and the unique quasisquare ${\mathrm{P}}_{4}$ units act as intermediaries and play an important role in promoting the Ruderman-Kittel-Kasuya-Yosida and superexchange interactions, respectively, which induces a robust ferrimagnetism. Our findings not only shed light on the promising future of 2D magnetic materials, but also are of interest for high-temperature spintronic applications.