Magnetism in 2D BN${}_{1-x}$O${}_x$ and B${}_{1-x}$Si${}_x$N: polarized itinerant and local electrons

Abstract

We use density functional theory based first-principles methods to study the magnetism in a 2D hexagonal BN sheet induced by the different concentrations of oxygen and silicon atoms substituting for nitrogen (O${}_{\mathrm{N}}$) and boron (Si${}_{\mathrm{B}}$) respectively. We demonstrate the possible formation of three distinct phases based on the magnetization energy calculated self-consistently for the ferromagnetic (ME${}_{\mathrm{FM}}$) and antiferromagnetic (ME${}_{\mathrm{AFM}}$) states, i.e. the paramagnetic phase with ME${}_{\mathrm{FM}}$=ME${}_{\mathrm{AFM}}$, the ferromagnetic phase with ME${}_{\mathrm{FM}}$$>$ME${}_{\mathrm{AFM}}$ and finally the polarized itinerant electrons with finite ME${}_{\mathrm{FM}}$ but zero ME${}_{\mathrm{AFM}}$. While the O${}_{\mathrm{N}}$ system was found to exist in all three phases, no tendency towards the formation of the polarized itinerant electrons was observed for the Si${}_{\mathrm{B}}$ system though the existence of the other two phases was ascertained. The different behavior of these two systems is associated with the diverse features in the magnetization energy as a function of the oxygen and silicon concentrations. Finally, the robustness of the polarized itinerant electron phase is also discussed with respect to the O substitute atom distributions and the applied strains to the system.

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References in corpus (4)

• Two Dimensional Atomic Crystals
• Magnetic Boron Nitride Nanoribbons with Tunable Electronic Properties
• Phase Diagram of the Low-Density Two-Dimensional Homogeneous Electron Gas
• Ab initio Studies of the Possible Magnetism in BN Sheet by Non-magnetic Impurities and Vacancies

Cited by in corpus (1)

• Functionalization of BN Honeycomb structure by Adsorption and Substitution of Foreign atoms