The antiferromagnetic phase of a wurtzite nickel sulfide monolayer.

Two-dimensional intrinsic long-range magnetic monolayers with high transition temperatures have attracted great interest in both fundamental studies and practical applications. In this study, we use a combination of first-principles calculations based on density functional theory (DFT), and unitary transformation of the effective Heisenberg model to investigate the electronic structure and magnetic properties of a [NiS] monolayer. The phonon calculations reveal that the [NiS] monolayer is dynamically stable in the wurtzite phase.

Robust ferromagnetism in two-dimensional GeC/CrN heterobilayers.

We have investigated the electronic and finite temperature magnetic properties of germanium carbide (GeC) and ferromagnetic chromium nitride (CrN) heterobilayers by using first-principles calculations based on density functional theory with Hubbard U correction and an effective anisotropic Heisenberg spin model. The dynamical stability of different stacking formations of heterobilayers is ensured by considering the phonon spectra. All the stacking patterns show half-metallicity with an out-of-plane easy-axis ferromagnetic ground state.

Easy-axis rotation in ferromagnetic monolayer CrN induced by fluorine and chlorine functionalization.

On the basis of first-principles calculations, we investigate the absorption of fluorine and chlorine on ferromagnetic monolayer CrN focusing on the mechanism of spin reorientation. We use density functional theory in combination with the spin Hamiltonian approach to study the electronic and magnetic properties of monolayer CrN upon single-side adsorption of F and Cl atoms. While the electronic structure of ferromagnetic CrN remains half-metallic after functionalization, its preferred axis of magnetization is rotated toward the in-plane direction due to the orbital moment suppression.

Electronic structure and optical properties of novel monolayer gallium nitride and boron phosphide heterobilayers.

Motivated by the increasing number of studies on optoelectronic applications of van der Waals (vdW) heterostructures, we have investigated the electronic and optical properties of monolayer gallium nitride (MGaN) and boron phosphide (MBP) heterobilayers by using first-principle calculations based on density functional theory. We have ensured the dynamical stability of the structures by considering their binding energies and phonon spectra. We show that the magnitude and status (direct or indirect) of the band gap are strongly dependent on the stacking pattern of the heterobilayers.

The effect of strain and functionalization on the optical properties of borophene.

Following its synthesis, borophene has drawn noticeable attention due to its remarkable intrinsic properties. Understanding and modifying these properties are crucial for implementation of borophene in high-technological applications. In this study, we employed ab initio techniques to examine the variation of the optoelectronic properties of buckled borophene by strain and surface functionalization.

Electronic and optical properties of boron phosphide/blue phosphorus heterostructures.

The van der Waals (vdW) heterostructures are emerging as promising structures for future possible optoelectronic devices. Motivated by the recent studies on vdW heterostructures with their fascinating physical properties, we investigate the electronic and optical properties of boron phosphide/blue phosphorus heterostructures in the framework of density functional theory (DFT) and tight-binding (TB) approximations. We analyze the variation of the energy band gap, the characteristics of the energy band diagram, charge redistribution by stacking and the electrostatic potential along the perpendicular direction.