The electronic, magnetic and optical properties of GaN monolayer doped with rare-earth elements

Structural, electronic, magnetic, and optical properties of rare earth (RE) metal element doped GaN monolayers are investigated using density functional theory, where RE = Nd, Sm, Eu, Gd, and Er. The introduction of RE atoms causes structural deformation of the GaN monolayer. The induced local magnetic moments are observed to be 4.00, 6.00, 7.00, 8.00, and 2.00 μB in Nd, Sm, Eu, Gd, and Er adsorbed GaN monolayers, respectively, while the values are 3.00, 5.00, 6.00, 7.00, and 3.00 μB in the substitution of Ga atoms. When Nd, Gd and Er adsorbed in GaN monolayer Fermi levels are shifted to the conduction band leading to metallicity, while in the case of Sm and Eu adsorption impurity states are found near the Fermi level. On the contrary, Eu, Gd and Er substitution of Ga atoms leads to the Fermi energy level being shifted below the VBM. In the Nd and Eu substitution system, the f-state is found near the Fermi level and the Nd-f state crosses the Fermi level. Optical absorption, transmission and refraction coefficients show that the addition of RE atoms can significantly enhance the prospects of GAN monolayers in visible as well as infrared applications. This research provides an outlook for the development of GaN monolayer-based optoelectronic as well as spintronics devices. •In comparison to GaN bulk materials, 2D GaN materials exhibit superior electronic, magnetic and optical properties.•Both substitution and adsorption doping methods were considered to study their electronic, magnetic and optical properties.•The f-state electrons (Nd, Sm, Eu, Gd, and Er) of rare earth elements exhibit large local magnetic moments.•RE atoms can significantly enhance the prospects of GAN monolayers in visible as well as infrared applications.