Hole-doping-induced half-metallic ferromagnetism in a highly-air-stable PdSe₂ monolayer under uniaxial stress

Abstract

Two-dimensional (2D) high-temperature ferromagnetic materials are important for spintronic application. Fortunately, a highly-air-stable PdSe2 monolayer semiconductor has been made through exfoliation from the layered bulk material. It is very highly desirable to realize robust ferromagnetism, even half-metallic ferromagnetism (100% spin polarization), in such excellent nonmagnetic monolayer semiconductors. Here, the first-principles investigation shows that the PdSe2 monolayer can be made to attain Stoner ferromagnetism with the maximal Curie temperature reaching to 800K, and the hole concentration threshold for ferromagnetism decreases with applied uniaxial stress. Furthermore, half-metallicity can be achieved in some hole concentration regions. For the strain of 10% (uniaxial tensile stress of 4.4 N/m), the monolayer can attain half-metallic ferromagnetism up to 150 K. The magnetic anisotropic energy is suitable to not only stabilizing the 2D ferromagnetism but also realizing fast magnetization reversal. The magnetization can be also controlled by applying a transverse uniaxial stress. The highly-air-stable PdSe2 monolayer, with these advantages, should be promising for spintronic applications.

Quasiparticle electronic structure and optical spectra of single-layer and bilayer PdSe2 : Proximity and defect-induced band gap renormalization

“…This is the result of the d 8 state of typical Pd 2+ complexes, which prefers to adopt square-planar coordination. The relaxed single layer PdSe 2 lowers the symmetry to the P2 1 /c space group with structural parameters of a=5.72, b=5.93 Å, and β=87.6°, which are in good agreement with previously reported theoretical [55] and experimental data [15,17]. The calculated total energy of the monolayer is 412 meV per formula unit is higher than that of bulk PdSe 2 and corresponds to the previously reported energy range (280-570 meV/PdSe 2 ) [13].…”

Pressure‐Tunable Ambipolar Conduction and Hysteresis in Thin Palladium Diselenide Field Effect Transistors

“…This important peculiarity of PdSe 2 could enhance its light absorption capability . The practical application of PdSe 2 can be further diversified by the strong spin–orbit coupling and the tunable topological quantum phase transitions, as well as by the induced ferromagnetism with Curie temperature beyond room temperature . Hence, 2D pentagonal PdSe 2 is very promising for the design of new functionalities in higher performance electronic devices that combine the charge, spin, and other degrees of freedom resulting from the low symmetry.…”

Robust p-orbital half-metallicity and high Curie-temperature in the hole-doped anisotropic TcX2 (X=SWu1, Yao2 2019Journal of Magnetism and Magnetic Materials15090View full textAdd to dashboardCite

“…It is found that the MAE can reach its maximum of 70.33 µeV per hole for the hole doping density ρ = 2.75 × 10 14 cm −2 . This is much larger than that of PdSe 2 monolayer (32 µeV per hole) [35]. Considering the MAE per area, the hole-doped TcS 2 monolayer has a value of 3.72µeVÅ −2 .…”